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Guo J, Wu YH, Zhang LX, Ji HR, Zhou N, Hu XY. [Clinical efficacy of nusinersen sodium in the treatment of children with spinal muscular atrophy]. ZHONGGUO DANG DAI ER KE ZA ZHI = CHINESE JOURNAL OF CONTEMPORARY PEDIATRICS 2024; 26:743-749. [PMID: 39014952 DOI: 10.7499/j.issn.1008-8830.2401082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 07/18/2024]
Abstract
OBJECTIVES To investigate the efficacy and safety of nusinersen sodium in the treatment of children with spinal muscular atrophy (SMA). METHODS A retrospective analysis was conducted on the clinical data of 50 children with 5q SMA who received nusinersen sodium treatment and multidisciplinary treatment management in Shanxi Children's Hospital from February 2022 to February 2024. RESULTS Compared with the baseline data, 67% (8/12), 74% (35/47), and 74% (35/47) of the SMA children had a clinically significant improvement in the scores of Philadelphia Infant Test of Neuromuscular Disorders, Hammersmith Functional Motor Scale Expanded, and Revised Upper Limb Module, respectively, and the distance of 6-minute walking test increased from 207.00 (179.00, 281.50) meters to 233.00 (205.25, 287.50) meters (P<0.05) after nusinersen sodium treatment. Of all 50 children with SMA, 24 (48%) showed good tolerability after administration, with no significant or persistent abnormalities observed in 2 034 laboratory test results, and furthermore, there were no serious or immunological adverse events related to the treatment. After treatment, there was a significant change in forced vital capacity as a percentage of the predicted value in 27 children with restrictive ventilatory dysfunction, as well as a significant change in the level of 25-(OH) vitamin D in 15 children with vitamin D deficiency (P<0.05). CONCLUSIONS For children with SMA, treatment with nusinersen sodium can continuously improve the response rates of motor function scales, with good tolerability and safety.
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Affiliation(s)
- Jin Guo
- Department of Neurology, Shanxi Medical University, Taiyuan 030000, China
| | | | | | - Hui-Ru Ji
- Department of Neurology, Shanxi Medical University, Taiyuan 030000, China
| | - Na Zhou
- Department of Neurology, Shanxi Medical University, Taiyuan 030000, China
| | - Xiao-Yue Hu
- Department of Neurology, Shanxi Medical University, Taiyuan 030000, China
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Ma K, Zhang K, Chen D, Wang C, Abdalla M, Zhang H, Tian R, Liu Y, Song L, Zhang X, Liu F, Liu G, Wang D. Real-world evidence: Risdiplam in a patient with spinal muscular atrophy type I with a novel splicing mutation and one SMN2 copy. Hum Mol Genet 2024; 33:1120-1130. [PMID: 38520738 PMCID: PMC11190614 DOI: 10.1093/hmg/ddae052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 03/08/2024] [Accepted: 03/08/2024] [Indexed: 03/25/2024] Open
Abstract
Spinal muscular atrophy (SMA), which results from the deletion or/and mutation in the SMN1 gene, is an autosomal recessive neuromuscular disorder that leads to weakness and muscle atrophy. SMN2 is a paralogous gene of SMN1. SMN2 copy number affects the severity of SMA, but its role in patients treated with disease modifying therapies is unclear. The most appropriate individualized treatment for SMA has not yet been determined. Here, we reported a case of SMA type I with normal breathing and swallowing function. We genetically confirmed that this patient had a compound heterozygous variant: one deleted SMN1 allele and a novel splice mutation c.628-3T>G in the retained allele, with one SMN2 copy. Patient-derived sequencing of 4 SMN1 cDNA clones showed that this intronic single transversion mutation results in an alternative exon (e)5 3' splice site, which leads to an additional 2 nucleotides (AG) at the 5' end of e5, thereby explaining why the patient with only one copy of SMN2 had a mild clinical phenotype. Additionally, a minigene assay of wild type and mutant SMN1 in HEK293T cells also demonstrated that this transversion mutation induced e5 skipping. Considering treatment cost and goals of avoiding pain caused by injections and starting treatment as early as possible, risdiplam was prescribed for this patient. However, the patient showed remarkable clinical improvements after treatment with risdiplam for 7 months despite carrying only one copy of SMN2. This study is the first report on the treatment of risdiplam in a patient with one SMN2 copy in a real-world setting. These findings expand the mutation spectrum of SMA and provide accurate genetic counseling information, as well as clarify the molecular mechanism of careful genotype-phenotype correlation of the patient.
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Affiliation(s)
- Kai Ma
- Pediatric Research Institute, Children’s Hospital Affiliated to Shandong University, Jingshi road NO. 23976, Jinan, SD 250022, PR China
- Department of neurology, Children’s Hospital Affiliated to Shandong University, Jingshi road NO. 23976, Jinan, SD 250022, PR China
| | - Kaihui Zhang
- Pediatric Research Institute, Children’s Hospital Affiliated to Shandong University, Jingshi road NO. 23976, Jinan, SD 250022, PR China
| | - Defang Chen
- The Office of operation management committee, Central Hospital Affiliated to Shandong First Medical University, Jiefang road NO. 105, Jinan, SD 250022, PR China
| | - Chuan Wang
- Science, Education and Foreign Affairs Section, Children’s Hospital Affiliated to Shandong University, Jingshi road NO. 23976, Jinan, SD 250022, PR China
| | - Mohnad Abdalla
- Pediatric Research Institute, Children’s Hospital Affiliated to Shandong University, Jingshi road NO. 23976, Jinan, SD 250022, PR China
| | - Haozheng Zhang
- Pediatric Research Institute, Children’s Hospital Affiliated to Shandong University, Jingshi road NO. 23976, Jinan, SD 250022, PR China
| | - Rujin Tian
- Pediatric Research Institute, Children’s Hospital Affiliated to Shandong University, Jingshi road NO. 23976, Jinan, SD 250022, PR China
| | - Yang Liu
- Pediatric Research Institute, Children’s Hospital Affiliated to Shandong University, Jingshi road NO. 23976, Jinan, SD 250022, PR China
- Ophthalmology department, Children’s Hospital Affiliated to Shandong University, Jingshi road NO. 23976, Jinan, SD 250022, PR China
| | - Li Song
- Pediatric Hematology and Oncology, Children’s Hospital Affiliated to Shandong University, Jingshi road NO. 23976, Jinan, SD 250022, PR China
| | - Xinyi Zhang
- Intensive Care Unit, The Second People’s Hospital of Shandong Province, Duanxing west road NO. 4, Jinan, SD 250022, PR China
| | - Fangfang Liu
- Department of Ultrasound, Central Hospital Affiliated to Shandong First Medical University, Jiefang road NO. 105, Jinan, SD 250022, PR China
| | - Guohua Liu
- Ophthalmology department, Children’s Hospital Affiliated to Shandong University, Jingshi road NO. 23976, Jinan, SD 250022, PR China
| | - Dong Wang
- Pediatric Research Institute, Children’s Hospital Affiliated to Shandong University, Jingshi road NO. 23976, Jinan, SD 250022, PR China
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Mattar CN, Chew WL, Lai PS. Embryo and fetal gene editing: Technical challenges and progress toward clinical applications. Mol Ther Methods Clin Dev 2024; 32:101229. [PMID: 38533521 PMCID: PMC10963250 DOI: 10.1016/j.omtm.2024.101229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/28/2024]
Abstract
Gene modification therapies (GMTs) are slowly but steadily making progress toward clinical application. As the majority of rare diseases have an identified genetic cause, and as rare diseases collectively affect 5% of the global population, it is increasingly important to devise gene correction strategies to address the root causes of the most devastating of these diseases and to provide access to these novel therapies to the most affected populations. The main barriers to providing greater access to GMTs continue to be the prohibitive cost of developing these novel drugs at clinically relevant doses, subtherapeutic effects, and toxicity related to the specific agents or high doses required. In vivo strategy and treating younger patients at an earlier course of their disease could lower these barriers. Although currently regarded as niche specialties, prenatal and preconception GMTs offer a robust solution to some of these barriers. Indeed, treating either the fetus or embryo benefits from economy of scale, targeting pre-pathological tissues in the fetus prior to full pathogenesis, or increasing the likelihood of complete tissue targeting by correcting pluripotent embryonic cells. Here, we review advances in embryo and fetal GMTs and discuss requirements for clinical application.
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Affiliation(s)
- Citra N.Z. Mattar
- Experimental Fetal Medicine Group, Department of Obstetrics and Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore, 1E Kent Ridge Road, NUHS Tower Block, Level 12, Singapore, Singapore 119228
- Department of Obstetrics and Gynaecology, National University Health System, Singapore, 1E Kent Ridge Road, NUHS Tower Block, Level 12, Singapore, Singapore 119228
| | - Wei Leong Chew
- Genome Institute of Singapore, Agency for Science, Technology and Research (A∗STAR), Singapore, 60 Biopolis St, Singapore, Singapore 138672
| | - Poh San Lai
- Department of Paediatrics, Yong Loo Lin School of Medicine, National University of Singapore, 1E Kent Ridge Road, NUHS Tower Block, Level 12, Singapore, Singapore 119228
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Yao M, Jiang L, Yan Y, Yu Y, Chen Y, Wang X, Feng Y, Cui Y, Zhou D, Gao F, Mao S. Analytical validation of the amplification refractory mutation system polymerase chain reaction-capillary electrophoresis assay to diagnose spinal muscular atrophy. Clin Chem Lab Med 2024; 0:cclm-2024-0334. [PMID: 38860968 DOI: 10.1515/cclm-2024-0334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2024] [Accepted: 05/26/2024] [Indexed: 06/12/2024]
Abstract
OBJECTIVES Spinal muscular atrophy (SMA) is a neuromuscular disorder caused by homozygous deletion and compound heterozygous mutations in survival motor neuron 1 (SMN1), with severity tied to the copy number of survival motor neuron 2 (SMN2). This study aimed to develop a rapid and comprehensive method for the diagnosis of SMA. METHODS A total of 292 children with clinically suspected SMA and 394 family members were detected by the amplification refractory mutation system polymerase chain reaction-capillary electrophoresis (ARMS-PCR-CE) method, which targeted 19 reported mutations, and the results were compared with those in multiplex ligation-dependent probe amplification (MLPA). Individuals with identified point mutations were further confirmed by SMN1 long-range PCR and Sanger sequencing. RESULTS A total of 202 children with SMA, 272 carriers, and 212 normal individuals were identified in this study. No difference was found in the R-value distribution of exons 7 and 8 in SMN1 and SMN2 among these cohorts, with coefficients of variation consistently below 0.08. To detect exon 7 and 8 copy numbers in SMN1 and SMN2, the ARMS-PCR-CE results were concordant with those of MLPA. Approximately 4.95 % (10/202) of the study patients had compound heterozygous mutations. CONCLUSIONS The ARMS-PCR-CE assay is a comprehensive, rapid, and accurate diagnostic method for SMA that simultaneously detects copy numbers of exons 7 and 8 in SMN1/SMN2, as well as 19 point mutations in SMN1 and 2 enhancers in SMN2. This approach can effectively reduce the time frame for diagnosis, facilitating early intervention and preventing birth defects.
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Affiliation(s)
- Mei Yao
- Department of Neurology, Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, P.R. China
- Department of Infectious Diseases, Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, P.R. China
| | - Liya Jiang
- Department of Neurology, Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, P.R. China
| | - Yue Yan
- Department of Neurology, Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, P.R. China
| | - Yicheng Yu
- Department of Neurology, Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, P.R. China
| | - Yuwei Chen
- Xiamen Biofast Biotechnology Co., Ltd., Xiamen, P.R. China
| | - Xiaoyi Wang
- Department of Neurology, Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, P.R. China
| | - Yijie Feng
- Department of Neurology, Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, P.R. China
| | - Yiqin Cui
- Department of Neurology, Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, P.R. China
| | - Dongming Zhou
- Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, P.R. China
| | - Feng Gao
- Department of Neurology, Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, P.R. China
| | - Shanshan Mao
- Department of Neurology, Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, P.R. China
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Zhou BB, Chen X, Zhang C, Wang YP, Ma PP, Hao SJ, Hui L, Bai YF. Analysis of spinal muscular atrophy carrier screening results in 32,416 pregnant women and 7,231 prepregnant women. Front Neurol 2024; 15:1357476. [PMID: 38654739 PMCID: PMC11035774 DOI: 10.3389/fneur.2024.1357476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Accepted: 03/28/2024] [Indexed: 04/26/2024] Open
Abstract
Objectives Spinal muscular atrophy (SMA) is an autosomal recessive disease that is one of the most common in childhood neuromuscular disorders. Our screenings are more meaningful programs in preventing birth defects, providing a significant resource for healthcare professionals, genetic counselors, and policymakers involved in designing strategies to prevent and manage SMA. Method We screened 39,647 participants from 2020 to the present by quantitative real-time PCR, including 7,231 pre-pregnancy participants and 32,416 pregnancy participants, to detect the presence of SMN1 gene EX7 and EX8 deletion in the DNA samples provided by the subjects. To validate the accuracy of our findings, we also utilized the Multiplex Ligation-dependent Probe Amplification (MLPA) to confirm the reliability of screening results obtained by quantitative real-time PCR. Result Among the 39,647 participants who were screened, 726 participants were the carriers of SMN1. The overall carrier rate was calculated to be 1.83% (95% confidence interval: 0.86-2.8%). After undergoing screening, a total of 592 pregnancy carriers were provided with genetic counseling and only 503 of their spouses (84.97, 95% confidence interval: 82.09-87.85%) voluntarily underwent SMA screening. Conclusion This study provides crucial insights into the prevalence and distribution of SMA carriers among the female population. The identification of 726 asymptomatic carriers highlights the necessity of comprehensive screening programs to identify at-risk individuals and ensure appropriate interventions are in place to minimize the impact of SMA-related conditions.
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Affiliation(s)
- Bing-bo Zhou
- State Key Laboratory of Digital Medical Engineering, School of Biological Science and Medical Engineering, Southeast University, Nanjing, China
- The Center for Medical Genetics in Gansu Provincial Maternity and Child-care Hospital, Gansu Provincial Clinical Research Center for Birth Defects and Rare Diseases, Lanzhou, China
| | - Xue Chen
- The Center for Medical Genetics in Gansu Provincial Maternity and Child-care Hospital, Gansu Provincial Clinical Research Center for Birth Defects and Rare Diseases, Lanzhou, China
| | - Chuan Zhang
- The Center for Medical Genetics in Gansu Provincial Maternity and Child-care Hospital, Gansu Provincial Clinical Research Center for Birth Defects and Rare Diseases, Lanzhou, China
| | - Yu-pei Wang
- The Center for Medical Genetics in Gansu Provincial Maternity and Child-care Hospital, Gansu Provincial Clinical Research Center for Birth Defects and Rare Diseases, Lanzhou, China
| | - Pan-pan Ma
- The Center for Medical Genetics in Gansu Provincial Maternity and Child-care Hospital, Gansu Provincial Clinical Research Center for Birth Defects and Rare Diseases, Lanzhou, China
| | - Sheng-ju Hao
- The Center for Medical Genetics in Gansu Provincial Maternity and Child-care Hospital, Gansu Provincial Clinical Research Center for Birth Defects and Rare Diseases, Lanzhou, China
| | - Ling Hui
- The Center for Medical Genetics in Gansu Provincial Maternity and Child-care Hospital, Gansu Provincial Clinical Research Center for Birth Defects and Rare Diseases, Lanzhou, China
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Sun H, Zheng J, Zhang Q, Ying F, Fu Y, Guan Y, Wu J, Zhou Y, Dong J, Xu M, Yang F, An N, Shi N, Zhang L, Zhu S, Liu J, Li M. Screening of Spinal Muscular Atrophy Carriers and Prenatal Diagnosis in Pregnant Women in Yancheng, China. Biochem Genet 2024:10.1007/s10528-024-10775-9. [PMID: 38581475 DOI: 10.1007/s10528-024-10775-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2023] [Accepted: 03/06/2024] [Indexed: 04/08/2024]
Abstract
Spinal muscular atrophy (SMA) is a neuromuscular disorder with an autosomal recessive inheritance pattern. Patients with severe symptoms may suffer respiratory failure, leading to death. The homozygous deletion of exon 7 in the SMN1 gene accounts for nearly 95% of all cases. Population carrier screening for SMA and prenatal diagnosis by amniocentesis for high-risk couples can assist in identifying the risk of fetal disease. We provided the SMA carrier screening process to 55,447 pregnant women in Yancheng from October 2020 to December 2022. Among them, 8185 participated in this process, with a participation rate of around 14.76% (95% CI 14.47-15.06%). Quantitative real-time polymerase chain reaction (qPCR) was used to detect deletions of SMN1 exons 7 and 8 (E7, E8) in screened pregnant women. 127 were identified as carriers (111 cases of E7 and E8 heterozygous deletions, 15 cases of E7 heterozygous deletions, and 1 case of E7 heterozygous deletions and E8 homozygous deletions), resulting in a carrying rate of around 1.55% (95% CI 1.30-1.84%). After genetic counseling, 114 spouses of pregnant women who tested positive underwent SMA carrier screening; three of them were screened as SMA carriers. Multiplexed ligation-dependent probe amplification (MLPA) was used for the prenatal diagnosis of the fetuses of high-risk couples. Two of them exhibited two copies of SMN1 exon 7 (normal), and the pregnancy was continued; one exhibited no copies of SMN1 exon 7 and exon 8 (SMA patient), and the pregnancy was terminated. Analyzing SMN1 mutations in Yancheng and provide clinical evidence for SMA genetic counseling and birth defect prevention. Interventional prenatal diagnosis for high-risk families can promote informed reproductive selection and prepare for the fetus's early treatment.
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Affiliation(s)
- Huilin Sun
- The Affiliated Yancheng Maternity&Child Health Hospital of Yangzhou University Medical School, Yancheng, 224001, China
| | - Jianli Zheng
- The Affiliated Yancheng Maternity&Child Health Hospital of Yangzhou University Medical School, Yancheng, 224001, China
| | - Qing'e Zhang
- The Affiliated Yancheng Maternity&Child Health Hospital of Yangzhou University Medical School, Yancheng, 224001, China
| | - Feifei Ying
- The Affiliated Yancheng Maternity&Child Health Hospital of Yangzhou University Medical School, Yancheng, 224001, China
| | - Yadong Fu
- The Affiliated Yancheng Maternity&Child Health Hospital of Yangzhou University Medical School, Yancheng, 224001, China
| | - Yongjuan Guan
- The Affiliated Yancheng Maternity&Child Health Hospital of Yangzhou University Medical School, Yancheng, 224001, China
| | - Jing Wu
- The Affiliated Yancheng Maternity&Child Health Hospital of Yangzhou University Medical School, Yancheng, 224001, China
| | - Yueyun Zhou
- The Affiliated Yancheng Maternity&Child Health Hospital of Yangzhou University Medical School, Yancheng, 224001, China
| | - Jingjing Dong
- The Affiliated Yancheng Maternity&Child Health Hospital of Yangzhou University Medical School, Yancheng, 224001, China
| | - Mengjun Xu
- The Affiliated Yancheng Maternity&Child Health Hospital of Yangzhou University Medical School, Yancheng, 224001, China
| | - Fangfang Yang
- The Affiliated Yancheng Maternity&Child Health Hospital of Yangzhou University Medical School, Yancheng, 224001, China
| | - Ning An
- The Affiliated Yancheng Maternity&Child Health Hospital of Yangzhou University Medical School, Yancheng, 224001, China
| | - Ning Shi
- The Affiliated Yancheng Maternity&Child Health Hospital of Yangzhou University Medical School, Yancheng, 224001, China
| | - Lu Zhang
- The Affiliated Yancheng Maternity&Child Health Hospital of Yangzhou University Medical School, Yancheng, 224001, China
| | - Shu Zhu
- The Affiliated Yancheng Maternity&Child Health Hospital of Yangzhou University Medical School, Yancheng, 224001, China
| | - Jianbing Liu
- The Affiliated Yancheng Maternity&Child Health Hospital of Yangzhou University Medical School, Yancheng, 224001, China.
| | - Min Li
- The Affiliated Yancheng Maternity&Child Health Hospital of Yangzhou University Medical School, Yancheng, 224001, China.
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Tan L, Qi Y, Zhao P, Cheng L, Yu G, Zhao D, Song YX, Xiang YG. Clinical application value of pre-pregnancy carrier screening in Chinese Han childbearing population. Mol Genet Genomic Med 2024; 12:e2425. [PMID: 38562051 PMCID: PMC10985407 DOI: 10.1002/mgg3.2425] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Revised: 02/29/2024] [Accepted: 03/19/2024] [Indexed: 04/04/2024] Open
Abstract
BACKGROUND To explore the clinical application value of pre-conception expanded carrier screening (PECS) in the Chinese Han ethnicity population of childbearing age. METHODS The results of genetic testing of infertile parents who underwent PECS in the Reproductive Medicine Center of the Second Affiliated Hospital of Zhengzhou University, China, from September 2019 to December 2021, were retrospectively analyzed. The carrier rate of single gene disease, the detection rate of high-risk parents, and the clinical outcome of high-risk parents were statistically analyzed. RESULTS A total of 1372 Chinese Han ethnicity patients underwent PECS, among which 458 patients underwent the extended 108-gene test, their overall carrier rate was 31.7%, and the detection rate of high-risk parents was 0.3%. The highest carrier rates were SLC22A (2.4%), ATP7B (2.4%), MMACHC (2.2%), PAH (1.8%), GALC (1.8%), MLC1 (1.3%), UNC13D (1.1%), CAPN3 (1.1%), and PKHD1 (1.1%). There were 488 women with fragile X syndrome-FMR1 gene detection, and 6 patients (1.2%) had FMR1 gene mutation. A total of 426 patients were screened for spinal muscular atrophy-SMN1, and the carrier rate was 3.5%, and the detection rate of parents' co-carrier was 0.5%. CONCLUSION Monogenic recessive hereditary diseases had a high carrier rate in the population. Pre-pregnancy screening could provide good prenatal and postnatal care guidance for patients and preimplantation genetic testing for monogenic/single gene disorders (PGT-M) and prenatal diagnosis could provide more precise reproductive choices for high-risk parents.
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Affiliation(s)
- Li Tan
- Department of Reproductive Medical CenterThe Second Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
| | - Yuefan Qi
- Department of Medical ImagingThe Second Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
| | - Peijuan Zhao
- Department of Reproductive GeneticsPingdingshan Maternal and Child Health HospitalPingdingshanChina
| | - LanLan Cheng
- Department of Reproductive Medical CenterThe Second Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
| | - Guo Yu
- Department of Reproductive Medical CenterThe Second Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
| | - Dongmei Zhao
- Department of Reproductive Medical CenterThe Second Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
| | - Yu Xia Song
- Department of Reproductive Medical CenterThe Second Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
| | - Yun Gai Xiang
- Department of Reproductive Medical CenterThe Second Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
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Chen HY, Lin SY, Shih JC, Kang J, Tai YY, Shaw SW, Chen KC, Mai K, Lee CN. Changing the standardised obstetric care by expanded carrier screening and counselling: a multicentre prospective cohort study. J Med Genet 2024; 61:176-181. [PMID: 37798098 DOI: 10.1136/jmg-2023-109268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Accepted: 09/05/2023] [Indexed: 10/07/2023]
Abstract
BACKGROUND Expanded genetic screening before conception or during prenatal care can provide a more comprehensive evaluation of heritable fetal diseases. This study aimed to provide a large cohort to evaluate the significance of expanded carrier screening and to consolidate the role of expanded genetic screening in prenatal care. METHODS This multicentre, retrospective cohort study was conducted between 31 December 2019 and 21 July 2022. A screening panel containing 302 genes and next-generation sequencing were used for the evaluation. The patients were referred from obstetric clinics, infertility centres and medical centres. Genetic counsellors conducted consultation for at least 15 min before and after screening. RESULTS A total of 1587 patients were screened, and 653 pairs were identified. Among the couples who underwent the screening, 62 (9.49%) had pathogenic variants detected on the same genes. In total, 212 pathogenic genes were identified in this study. A total of 1173 participants carried at least one mutated gene, with a positive screening rate of 73.91%. Among the pathogenic variants that were screened, the gene encoding gap junction beta-2 (GJB2) exhibited the highest prevalence, amounting to 19.85%. CONCLUSION Next-generation sequencing carrier screening provided additional information that may alter prenatal obstetric care by 9.49%. Pan-ethnic genetic screening and counselling should be suggested for couples of fertile age.
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Affiliation(s)
- Han-Ying Chen
- Department of Obstetrics and Gynecology, National Taiwan University Hospital, Taipei, Taiwan
- Program for Precision Health and Intelligent Medicine, Graduate School of Advanced Technology, National Taiwan University, Taipei, Taiwan
| | - Shin-Yu Lin
- Department of Obstetrics and Gynecology, National Taiwan University Hospital, Taipei, Taiwan
| | - Jin-Chung Shih
- Department of Obstetrics and Gynecology, National Taiwan University Hospital, Taipei, Taiwan
| | - Jessica Kang
- Department of Obstetrics and Gynecology, National Taiwan University Hospital, Taipei, Taiwan
| | - Yi-Yun Tai
- Department of Medical Genetics, National Taiwan University Hospital, Taipei, Taiwan
| | - Steven W Shaw
- Department of Obstetrics and Gynecology, Taipei Chang Gung Memorial Hospital, Taipei, Taiwan
- College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Kuang-Cheng Chen
- College of Osteopathic Medicine of the Pacific, Western University of Health Sciences, Pomona, California, USA
| | - Kevin Mai
- College of Osteopathic Medicine of the Pacific, Western University of Health Sciences, Pomona, California, USA
| | - Chien-Nan Lee
- Department of Obstetrics and Gynecology, National Taiwan University Hospital, Taipei, Taiwan
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9
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Abiusi E, Costa-Roger M, Bertini ES, Tiziano FD, Tizzano EF, Abiusi E, Baranello G, Bertini E, Boemer F, Burghes A, Codina-Solà M, Costa-Roger M, Dangouloff T, Groen E, Gos M, Jędrzejowska M, Kirschner J, Lemmink HH, Müller-Felber W, Ouillade MC, Quijano-Roy S, Rucinski K, Saugier-Veber P, Tiziano FD, Tizzano EF, Wirth B. 270th ENMC International Workshop: Consensus for SMN2 genetic analysis in SMA patients 10-12 March, 2023, Hoofddorp, the Netherlands. Neuromuscul Disord 2024; 34:114-122. [PMID: 38183850 DOI: 10.1016/j.nmd.2023.12.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2024]
Abstract
The 270th ENMC workshop aimed to develop a common procedure to optimize the reliability of SMN2 gene copy number determination and to reinforce collaborative networks between molecular scientists and clinicians. The workshop involved neuromuscular and clinical experts and representatives of patient advocacy groups and industry. SMN2 copy number is currently one of the main determinants for therapeutic decision in SMA patients: participants discussed the issues that laboratories may encounter in this molecular test and the cruciality of the accurate determination, due the implications as prognostic factor in symptomatic patients and in individuals identified through newborn screening programmes. At the end of the workshop, the attendees defined a set of recommendations divided into four topics: SMA molecular prognosis assessment, newborn screening for SMA, SMN2 copies and treatments, and modifiers and biomarkers. Moreover, the group draw up a series of recommendations for the companies manufacturing laboratory kits, that will help to minimize the risk of errors, regardless of the laboratories' expertise.
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Affiliation(s)
- Emanuela Abiusi
- Section of Genomic Medicine, Department of Public Health and Life Sciences, Università Cattolica del Sacro Cuore, Roma, Italy
| | - Mar Costa-Roger
- Clinical and Molecular Genetics Area, Vall d'Hebron Hospital; Medicine Genetics Group, Vall d'Hebron Research Institute (VHIR), Barcelona, Spain
| | - Enrico Silvio Bertini
- Research Unit of Neuromuscular Disease, Bambino Gesu’ Children's Hospital, IRCCS, Roma, Italy
| | - Francesco Danilo Tiziano
- Section of Genomic Medicine, Department of Public Health and Life Sciences, Università Cattolica del Sacro Cuore, Roma, Italy
- Complex Unit of Medical Genetics, Fondazione Policlinico Universitario IRCCS “A. Gemelli”, Roma, Italy
| | - Eduardo F Tizzano
- Clinical and Molecular Genetics Area, Vall d'Hebron Hospital; Medicine Genetics Group, Vall d'Hebron Research Institute (VHIR), Barcelona, Spain
| | - Emanuela Abiusi
- Section of Genomic Medicine, Dept. of Life Sciences and Public Health, Catholic University of the Sacred Heart, Roma, Italy
| | - Giovanni Baranello
- The Dubowitz Neuromuscular Centre, Developmental Neuroscience Research and Teaching Department, UCL Great Ormond Street Institute of Child Health, NIHR Great Ormond Street Hospital Biomedical Research Centre & Great Ormond Street Hospital NHS Foundation Trust, 30 Guilford Street, London WC1N 1EH, UK
| | - Enrico Bertini
- Italy, Research Unit of Neuromuscular Disease, Bambino Gesù Children's Hospital, IRCCS, Roma, Italy
| | - François Boemer
- Biochemical Genetics Lab, Department of Human Genetics, University Hospital, University of Liège, 4000 Liège, Belgium
| | - Arthur Burghes
- Department of Neurology, The Ohio State University Wexner Medical Center, Columbus, OH, USA
| | - Marta Codina-Solà
- Neuromuscular Reference Center, Department of Paediatrics, University Hospital Liege & University of Liege, Belgium
| | - Mar Costa-Roger
- Department of Neurology & Neurosurgery, UMC Utrecht Brain Center, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Tamara Dangouloff
- Department of Medical Genetics, Institute of Mother and Child, Warsaw, Poland
| | - Ewout Groen
- Department of Neurology, Medical University of Warsaw, Warsaw, Poland
| | - Monika Gos
- Department of Neuropediatrics and Muscle Disorders, Medical Center University of Freiburg, Faculty of Medicine, Freiburg, Germany
| | - Maria Jędrzejowska
- Department of Genetics, University of Groningen, University Medical Center Groningen, 9700 RB Groningen, The Netherlands
| | - Janbernd Kirschner
- Centre for Neuromuscular Disorders, Center for Translational Neuro and Behavioral Sciences, Department of Pediatric Neurology, University Duisburg-Essen, 45147 Essen, Germany
| | - Henny H Lemmink
- AFM Téléthon, Évry, France; SMA Europe; European Alliance for Newborn Screening in Spinal Muscular Atrophy
| | - Wolfgang Müller-Felber
- Pediatric Neuromuscular Unit (NEIDF Reference Center at FILNEMUS & Euro-NMD), Child Neurology Department, Raymond Poincaré Hospital (UVSQ), APHP Université Paris Saclay, Garches France
| | - Marie-Christine Ouillade
- Fundacja SMA, Warsaw, Poland; SMA Europe; European Alliance for Newborn Screening in Spinal Muscular Atrophy
| | - Susana Quijano-Roy
- Univ Rouen Normandie, Inserm U1245, Normandie Univ and CHU Rouen, Department of Genetics and Nord/Est/Ile de France Neuromuscular Reference Center, F-76000 Rouen, France
| | - Kacper Rucinski
- Institute of Medical Genomics, Dept. of Life Sciences and Public Health, Catholic University of the Sacred Heart, and Complex Unit of Medical Genetics, Fondazione Policlinico Universitario IRCCS “A. Gemelli”, Roma, Italy
| | - Pascale Saugier-Veber
- Institute of Human Genetics, University Hospital of Cologne, Center for Molecular Medicine, University of Cologne and Center for Rare Diseases Cologne, University Hopsital of Cologne, Cologne, Germany
| | - Francesco Danilo Tiziano
- Institute of Medical Genomics, Dept. of Life Sciences and Public Health, Catholic University of the Sacred Heart, and Complex Unit of Medical Genetics, Fondazione Policlinico Universitario IRCCS “A. Gemelli”, Roma, Italy
| | - Eduardo Fidel Tizzano
- Clinical and Molecular Genetics Area, Vall d'Hebron Hospital; Medicine Genetics Group, Vall d'Hebron Research Institute (VHIR), Barcelona, Spain
| | - Brunhilde Wirth
- Institute of Human Genetics, University Hospital of Cologne, Center for Molecular Medicine, University of Cologne and Center for Rare Diseases Cologne, University Hopsital of Cologne, Cologne, Germany
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Sun Y, Ma S, Xiao J, Wu J, Wu Y, Shi X, Li S, Feng L, Chen S. Preconception or prenatal acceptance of SMN1 gene carrier screening and carrier rate of spinal muscular atrophy: a retrospective study in 18,818 reproductive age women in Wuhan area of China. J Assist Reprod Genet 2024; 41:127-133. [PMID: 37991656 PMCID: PMC10789693 DOI: 10.1007/s10815-023-02991-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2023] [Accepted: 11/06/2023] [Indexed: 11/23/2023] Open
Abstract
OBJECTIVE Spinal muscular atrophy (SMA) is an autosomal recessive disorder mainly affecting the neuromuscular system, which seriously threatens the life and health of patients. But few studies have reported the acceptance rate of SMA gene screening and SMA carrier rate in China. The present study aimed to clarify the two issues in China through a retrospective analysis of 18,818 reproductive age women in Wuhan area of China. METHODS The copy number (CN) of exons 7 and 8 in survival motor neuron 1 (SMN1) gene was detected by real-time quantitative PCR, and the results were verified by multiplex ligation-dependent probe amplification. RESULTS Carrier screening was offered to 44,953 women of childbearing age in our medical center from March, 2018, to February, 2022, of whom 18,818 were enrolled in the program. A total of 336 women were identified as carriers (1.73%; 326/18,808; without fertility history of the children with SMA). Among 18,818 reproductive age women, 286 spouses (85.12%; 286/336) were successfully recalled for screening. The results showed 17 couples at high risk of having children with SMA, of whom prenatal diagnosis was implemented in 11, and 6 fetuses were identified with SMA. All the 5 pregnant women bearing the 6 SMA fetuses chose to terminate the pregnancy by artificial abortion. CONCLUSION Reproductive age women and their spouses in Wuhan area showed a positive attitude toward general screening for SMA carriers. Given the high early mortality of children with SMA, screening for SMA carriers in women of reproductive age is necessary and feasible.
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Affiliation(s)
- Yanan Sun
- Department of Obstetrics and Gynecology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, Hubei, China
| | - Songyan Ma
- Department of Obstetrics and Gynecology, Wuhan Children's Hospital (Wuhan Maternal and Child Healthcare Hospital), Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430015, Hubei, China
| | - Juan Xiao
- Department of Obstetrics and Gynecology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, Hubei, China
| | - Jianli Wu
- Department of Obstetrics and Gynecology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, Hubei, China
| | - Yuanyuan Wu
- Department of Obstetrics and Gynecology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, Hubei, China
| | - Xinwei Shi
- Department of Obstetrics and Gynecology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, Hubei, China
| | - Shufang Li
- Department of Obstetrics and Gynecology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, Hubei, China
| | - Ling Feng
- Department of Obstetrics and Gynecology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, Hubei, China
| | - Suhua Chen
- Department of Obstetrics and Gynecology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, Hubei, China.
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Feng Y, Jin J, Chen T, Wang J, Jiang Y, Gao F, Mao S. Efficacy and safety of salbutamol in treatment of children with later-onset spinal muscular atrophy. Zhejiang Da Xue Xue Bao Yi Xue Ban 2023; 52:714-720. [PMID: 38105669 PMCID: PMC10764179 DOI: 10.3724/zdxbyxb-2023-0463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Accepted: 12/10/2023] [Indexed: 12/19/2023]
Abstract
OBJECTIVES To investigate the clinical efficacy and safety of salbutamol in the treatment of children with later-onset spinal muscular atrophy (SMA). METHODS This study is a prospective single-arm phase Ⅲ clinical study. Pediatric patients with SMA type Ⅱ and Ⅲ who visited Department of Neurology, Children's Hospital, Zhejiang University School of Medicine from December 2020 to June 2022 were enrolled. All patients were evaluated with motor function scales, pulmonary function test and drug safety before study. Patients were treated with salbutamol tablets orally, with an initial dose of 1 mg (tid). If tolerable, the dose was increased to 1.5 mg (tid) in the second week, then increased to 2 mg (tid) from the third week and maintained for 6 months. Patients were followed up at 1, 3 and 6 months of treatment. RESULTS Twenty-six patients were enrolled, including 10 boys and 16 girls. There were 16 cases of SMA type Ⅱ and 10 cases of type Ⅲ with age at treatment initiation of 5.67 (3.13, 7.02) years and disease duration of 2.54 (1.31, 4.71) years. The Hammersmith Functional Motor Scale-Expanded (HFMSE) scores were increased from 14.0 (6.5, 43.0) before treatment to 26.0 (15.0, 46.5) after treatment (Z=-4.144, P<0.01) in 25 cases. The Revised Upper Limb Module Scale scores were increased from 33.0 (25.5, 36.0) before treatment to 35.0 (31.0, 36.5) after treatment (Z=-2.214, P<0.05) in 9 cases. In 7 ambulant children with SMA type Ⅲ, the six minutes walking distance was increased by 30 (15, 52) m after a 6-month treatment (Z=-2.366, P<0.05). Compared with the baseline pulmonary functions the patients showed a significant increase in forced vital capacity (FVC), forced expiratory volume in one second (FEV1), and peak expiratory flow (PEF) in 15 cases after treatment (all P<0.05). According to patients and caregivers subjective reporting, there were various degrees of improvement in coughing, sputum production ability and exercise endurance. No serious adverse events were observed during the study. CONCLUSIONS Short-term oral administration of salbutamol may improve motor and pulmonary functions in later-onset SMA children with good safety.
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Affiliation(s)
- Yijie Feng
- Department of Neurology, Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou 310052, China.
| | - Jianing Jin
- Department of Neurology, Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou 310052, China
| | - Tingting Chen
- Department of Developmental Behavior, Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou 310052, China
| | - Jianhua Wang
- Department of Respiratory Medicine, Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou 310052, China
| | - Yuan Jiang
- Department of Respiratory Medicine, Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou 310052, China
| | - Feng Gao
- Department of Neurology, Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou 310052, China
| | - Shanshan Mao
- Department of Neurology, Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou 310052, China.
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12
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Chan SHS, Wong CKH, Wu T, Wong W, Yu MKL, Au ICH, Chan GCF. Significant healthcare burden and life cost of spinal muscular atrophy: real-world data. THE EUROPEAN JOURNAL OF HEALTH ECONOMICS : HEPAC : HEALTH ECONOMICS IN PREVENTION AND CARE 2023; 24:1373-1382. [PMID: 36403177 PMCID: PMC10533630 DOI: 10.1007/s10198-022-01548-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Accepted: 11/07/2022] [Indexed: 06/16/2023]
Abstract
OBJECTIVES The aim of this study is to quantify the mortality rate, direct healthcare costs, and cumulative life costs of pediatric patients with spinal muscular atrophy (SMA) type 1, type 2, and type 3 born in Hong Kong. METHODS Data were collected from genetically confirmed SMA patients born in or after 2000 from the Hospital Authority medical database. Patients were followed up from birth until they died, left Hong Kong, reached 18 years, or initiated disease-modifying treatment. Study outcomes included incidence risks of mortality, cumulative direct medical costs-attendances of special outpatient clinics, emergency department, allied health services, and mean length of stay in hospitals over time. Total direct medical costs were calculated as unit costs multiplied by utilization frequencies of corresponding healthcare services at each age. RESULTS Seventy-one patients with SMA were included. Over a median follow-up period of 6 years, the overall incidence rate of death was 5.422/100 person-years (95%CI 3.542-7.945/100 person-years). 67.7% and 11% of deaths occurred in SMA1 and SMA2 groups, respectively. The median age of death was 0.8 years in SMA1 and 10.9 years in SMA2. The mean cumulative direct medical costs in overall SMA, SMA1, SMA2 and SMA3 groups per patient were US$935,570, US$2,393,250, US$413,165, and US$40,735, respectively. INTERPRETATION Our results confirmed a significantly raised mortality and extremely high healthcare burden for patients with SMA especially SMA type 1 and 2 without disease-modifying treatment. Study evaluating health and economic impact of newborn screening and early treatment is needed.
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Affiliation(s)
- Sophelia H S Chan
- Department of Paediatrics and Adolescent Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong Special Administrative Region, China.
| | - Carlos K H Wong
- Department of Pharmacology and Pharmacy, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong Special Administrative Region, China.
- Department of Family Medicine and Primary Care, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China.
| | - Tingting Wu
- Department of Family Medicine and Primary Care, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - Wilfred Wong
- Department of Paediatrics and Adolescent Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong Special Administrative Region, China
| | - Michael K L Yu
- Department of Paediatrics and Adolescent Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong Special Administrative Region, China
| | - Ivan C H Au
- Department of Pharmacology and Pharmacy, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong Special Administrative Region, China
| | - Godfrey C F Chan
- Department of Paediatrics and Adolescent Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong Special Administrative Region, China
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Carrier Screening Programs for Cystic Fibrosis, Fragile X Syndrome, Hemoglobinopathies and Thalassemia, and Spinal Muscular Atrophy: A Health Technology Assessment. ONTARIO HEALTH TECHNOLOGY ASSESSMENT SERIES 2023; 23:1-398. [PMID: 37637488 PMCID: PMC10453298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 08/29/2023]
Abstract
Background We conducted a health technology assessment to evaluate the safety, effectiveness, and cost-effectiveness of carrier screening programs for cystic fibrosis (CF), fragile X syndrome (FXS), hemoglobinopathies and thalassemia, and spinal muscular atrophy (SMA) in people who are considering a pregnancy or who are pregnant. We also evaluated the budget impact of publicly funding carrier screening programs, and patient preferences and values. Methods We performed a systematic literature search of the clinical evidence. We assessed the risk of bias of each included study using the Cochrane Risk of Bias tool and the Risk of Bias Assessment tool for Non-randomized Studies (RoBANS), and the quality of the body of evidence according to the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) Working Group criteria. We performed a systematic economic literature search and conducted cost-effectiveness analyses comparing preconception or prenatal carrier screening programs to no screening. We considered four carrier screening strategies: 1) universal screening with standard panels; 2) universal screening with a hypothetical expanded panel; 3) risk-based screening with standard panels; and 4) risk-based screening with a hypothetical expanded panel. We also estimated the 5-year budget impact of publicly funding preconception or prenatal carrier screening programs for the given conditions in Ontario. To contextualize the potential value of carrier screening, we spoke with 22 people who had sought out carrier screening. Results We included 107 studies in the clinical evidence review. Carrier screening for CF, hemoglobinopathies and thalassemia, FXS, and SMA likely results in the identification of couples with an increased chance of having an affected pregnancy (GRADE: Moderate). Screening likely impacts reproductive decision-making (GRADE: Moderate) and may result in lower anxiety among pregnant people, although the evidence is uncertain (GRADE: Very low).We included 21 studies in the economic evidence review, but none of the study findings were directly applicable to the Ontario context. Our cost-effectiveness analyses showed that in the short term, preconception or prenatal carrier screening programs identified more at-risk pregnancies (i.e., couples that tested positive) and provided more reproductive choice options compared with no screening, but were associated with higher costs. While all screening strategies had similar values for health outcomes, when comparing all strategies together, universal screening with standard panels was the most cost-effective strategy for both preconception and prenatal periods. The incremental cost-effectiveness ratios (ICERs) of universal screening with standard panels compared with no screening in the preconception period were $29,106 per additional at-risk pregnancy detected and $367,731 per affected birth averted; the corresponding ICERs in the prenatal period were about $29,759 per additional at-risk pregnancy detected and $431,807 per affected birth averted.We estimated that publicly funding a universal carrier screening program in the preconception period over the next 5 years would require between $208 million and $491 million. Publicly funding a risk-based screening program in the preconception period over the next 5 years would require between $1.3 million and $2.7 million. Publicly funding a universal carrier screening program in the prenatal period over the next 5 years would require between $128 million and $305 million. Publicly funding a risk-based screening program in the prenatal period over the next 5 years would require between $0.8 million and $1.7 million. Accounting for treatment costs of the screened health conditions resulted in a decrease in the budget impact of universally provided carrier screening programs or cost savings for risk-based programs.Participants value the perceived potential positive impact of carrier screening programs such as medical benefits from early detection and treatment, information for reproductive decision-making, and the social benefit of awareness and preparation. There was a strong preference expressed for thorough, timely, unbiased information to allow for informed reproductive decision-making. Conclusions Carrier screening for CF, FXS, hemoglobinopathies and thalassemia, and SMA is effective at identifying at-risk couples, and test results may impact preconception and reproductive decision-making.The cost-effectiveness and budget impact of carrier screening programs are uncertain for Ontario. Over the short term, carrier screening programs are associated with higher costs, and also higher chances of detecting at-risk pregnancies compared with no screening. The 5-year budget impact of publicly funding universal carrier screening programs is larger than that of risk-based programs. However, accounting for treatment costs of the screened health conditions results in a decrease in the total additional costs for universal carrier screening programs or in cost savings for risk-based programs.The people we spoke with who had sought out carrier screening valued the potential medical benefits of early detection and treatment, particularly the support and preparation for having a child with a potential genetic condition.
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Mikhalchuk K, Shchagina O, Chukhrova A, Zabnenkova V, Chausova P, Ryadninskaya N, Vlodavets D, Kutsev SI, Polyakov A. Pilot Program of Newborn Screening for 5q Spinal Muscular Atrophy in the Russian Federation. Int J Neonatal Screen 2023; 9:29. [PMID: 37218894 PMCID: PMC10204550 DOI: 10.3390/ijns9020029] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 05/02/2023] [Accepted: 05/11/2023] [Indexed: 05/24/2023] Open
Abstract
5q spinal muscular atrophy (5q SMA) is one of the most common autosomal recessive disorders in the Russian Federation. The first medication to treat 5q SMA was registered in the Russian Federation for treatment of all 5q SMA types in 2019, and the last of the three currently available in December 2021. We launched the pilot newborn screening (NBS) program for 5q SMA in Moscow, the Russian Federation, starting in 2019. During the pilot program, 23,405 neonates were tested for the deletion of exon 7 of the SMN1 gene, the most common cause of 5q SMA. We used the SALSA® MC002 SMA Newborn Screen Kit (MRC Holland) to specifically detect homozygous deletions of SMN1 exon 7. We used the restriction fragment length polymorphism (RFLP) approach to validate detected homozygous deletions and the SALSA MLPA Probemix P060 SMA Carrier Kit (MRC Holland) to determine the SMN2 exon 7 copy number to prescribe gene therapy for 5q SMA. Three newborns with a homozygous deletion of the SMN1 gene were detected. The calculated birth prevalence of 1:7801 appears to be similar to the results in other European countries. The children did not show any signs of respiratory involvement or bulbar weakness immediately after birth. Until now, no 5q SMA case missed by NBS has been detected.
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Affiliation(s)
- Kristina Mikhalchuk
- Research Centre for Medical Genetics, Moskvorechye St., 1, 115522 Moscow, Russia
| | - Olga Shchagina
- Research Centre for Medical Genetics, Moskvorechye St., 1, 115522 Moscow, Russia
| | - Alena Chukhrova
- Research Centre for Medical Genetics, Moskvorechye St., 1, 115522 Moscow, Russia
| | - Viktoria Zabnenkova
- Research Centre for Medical Genetics, Moskvorechye St., 1, 115522 Moscow, Russia
| | - Polina Chausova
- Research Centre for Medical Genetics, Moskvorechye St., 1, 115522 Moscow, Russia
| | - Nina Ryadninskaya
- Research Centre for Medical Genetics, Moskvorechye St., 1, 115522 Moscow, Russia
| | - Dmitry Vlodavets
- Russian Children Neuromuscular Center, Veltischev Clinical Pediatric Research Institute, Pirogov Russian National Research Medical University, Taldomskaya Str. 2, 125412 Moscow, Russia
| | - Sergei I. Kutsev
- Research Centre for Medical Genetics, Moskvorechye St., 1, 115522 Moscow, Russia
| | - Alexander Polyakov
- Research Centre for Medical Genetics, Moskvorechye St., 1, 115522 Moscow, Russia
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Huang Z, Yang Q, Ye J, Huang J, Lin J, Chen J, Liang Z, Cao Z. Screening and prenatal diagnosis of survival motor neuron gene deletion in pregnant women in Zhaoqing city, Guangdong Province. BMC Med Genomics 2023; 16:39. [PMID: 36859245 PMCID: PMC9976494 DOI: 10.1186/s12920-023-01468-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Accepted: 02/22/2023] [Indexed: 03/03/2023] Open
Abstract
OBJECTIVE A total of 5,200 pregnant women in Zhaoqing city, Guangdong Province, were screened to identify spinal muscular atrophy (SMA) mutation carriers to guide the prevention of SMA and prevent the birth of children with SMA. METHODS Exons 7 and 8 (E7 and E8) of the survival motor neuron (SMN) 1 gene were detected in women using real-time fluorescence quantitative polymerase chain reaction. SMN1 and SMN2 copy numbers in those who were initially identified as carriers were verified via targeted region capture and next-generation sequencing. When both partners were identified as carriers, prenatal diagnosis of the fetus was performed. RESULTS Among the screened women, 75 SMA carriers (71 cases had both E7 and E8 heterozygous deletions and 4 cases only had an E7 heterozygous deletion) were identified, with a carrier frequency of 1.44% (95% confidence interval: 1.31-1.65%). Three couples where both spouses were identified as SMA carriers, and their three fetuses were subjected to prenatal genetic analysis. Of the three, one had homozygous deletions of E7 and E8 and the other two had heterozygous deletions of E7 and E8. After a detailed prenatal consultation, the former couple decided to terminate the pregnancy. CONCLUSION Through screening and prenatal diagnosis of pregnant women in Zhaoqing city, Guangdong Province, the incidence of SMA can be reduced, prevention of birth defects can be improved, incidence of birth defects can be effectively minimized.
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Affiliation(s)
- Zhiwei Huang
- Clinical Laboratory, The Second People's Hospital of Zhaoqing, Zhaoqing, The People's Republic of China. .,Clinical Laboratory, The Second People's Hospital of Zhaoqing, Zhaoqing, The People's Republic of China. .,Clinical Laboratory, The Second People's Hospital of Zhaoqing, No. 2, Jiansheer Street, 526000, Zhaoqing City, Guangdong province, The People's Republic of China.
| | - Qingchan Yang
- Clinical Laboratory, The Second People's Hospital of Zhaoqing, Zhaoqing, The People's Republic of China
| | - Jianxiang Ye
- Clinical Laboratory, The Second People's Hospital of Zhaoqing, Zhaoqing, The People's Republic of China
| | - Jianxing Huang
- Clinical Laboratory, The Second People's Hospital of Zhaoqing, Zhaoqing, The People's Republic of China
| | - Jin Lin
- Obstetrical Department, The Second People's Hospital of Zhaoqing, Zhaoqing, The People's Republic of China
| | - Jing Chen
- Prenatal Diagnosis Center, The Second People's Hospital of Zhaoqing, Zhaoqing, The People's Republic of China
| | - Zizhao Liang
- Clinical Laboratory, The Second People's Hospital of Zhaoqing, Zhaoqing, The People's Republic of China
| | - Zijie Cao
- Clinical Laboratory, The Second People's Hospital of Zhaoqing, Zhaoqing, The People's Republic of China
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Li Y, Wang L, Tan J, Huang M, Wang Y, Shao B, Lv J, Zhang J. Current attitudes toward carrier screening for spinal muscular atrophy among pregnant women in Eastern China. J Genet Couns 2023. [PMID: 36775845 DOI: 10.1002/jgc4.1691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Revised: 01/05/2023] [Accepted: 01/28/2023] [Indexed: 02/14/2023]
Abstract
Spinal muscular atrophy (SMA) is an autosomal recessive and often fatal neurological disease. However, very little is known about the attitudes toward SMA carrier screening among Chinese pregnant people. In this study, pregnant women in Eastern China who were undergoing routine chromosomal screening programs were invited to view an educational video about SMA and complete a 26-item survey regarding their attitudes toward SMA screening by scanning a specific quick response code. A total of 1673 questionnaires were collected, and 81.1% of respondents were willing to undergo self-funded screening. If the screening program were included in the medical insurance, 97.8% of respondents were willing to accept screening. The important reasons for supporting SMA screening were a belief that it could help them make better reproductive decisions and avoid having a child with SMA. The key reason for declining SMA screening was not having a family history of genetic diseases. A higher score for SMA genetics knowledge was associated with a greater willingness to undergo SMA screening. We concluded that pregnant women in Eastern China had positive attitudes toward SMA carrier screening. Improving genetic knowledge and including the screening program in medical insurance would support the widespread implementation of SMA carrier screening. Steps should be taken to offer SMA carrier screening along with pre- and posttest education and genetic counseling to raise awareness and reduce misconceptions regarding SMA.
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Affiliation(s)
- Yerong Li
- Department of Prenatal diagnosis, Women's Hospital of Nanjing Medical University, Nanjing Maternity and Child Health Care Hospital, Nanjing, China
| | - Lulu Wang
- Department of Prenatal diagnosis, Women's Hospital of Nanjing Medical University, Nanjing Maternity and Child Health Care Hospital, Nanjing, China
| | - Jianxin Tan
- Department of Prenatal diagnosis, Women's Hospital of Nanjing Medical University, Nanjing Maternity and Child Health Care Hospital, Nanjing, China
| | - Mingtao Huang
- Department of Prenatal diagnosis, Women's Hospital of Nanjing Medical University, Nanjing Maternity and Child Health Care Hospital, Nanjing, China
| | - Yuguo Wang
- Department of Prenatal diagnosis, Women's Hospital of Nanjing Medical University, Nanjing Maternity and Child Health Care Hospital, Nanjing, China
| | - Binbin Shao
- Department of Prenatal diagnosis, Women's Hospital of Nanjing Medical University, Nanjing Maternity and Child Health Care Hospital, Nanjing, China
| | - Juan Lv
- Department of Gynecology, Women's Hospital of Nanjing Medical University, Nanjing Maternity and Child Health Care Hospital, Nanjing, China
| | - Jingjing Zhang
- Department of Prenatal diagnosis, Women's Hospital of Nanjing Medical University, Nanjing Maternity and Child Health Care Hospital, Nanjing, China
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Edwards S, Laing N. Genetic Counselling Needs for Reproductive Genetic Carrier Screening: A Scoping Review. J Pers Med 2022; 12:1699. [PMID: 36294838 PMCID: PMC9605645 DOI: 10.3390/jpm12101699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Revised: 10/03/2022] [Accepted: 10/08/2022] [Indexed: 11/17/2022] Open
Abstract
Reproductive genetic carrier screening provides individuals and couples with information regarding their risk of having a child affected by an autosomal recessive or X-linked recessive genetic condition. This information allows them the opportunity to make reproductive decisions in line with their own beliefs and values. Traditionally, carrier screening has been accessed by family members of affected individuals. In recent years, improvements to accessibility and updates to recommendations suggest that all women planning or in early pregnancy should be offered reproductive genetic carrier screening. As uptake moves towards the population scale, how can the genetic counselling needs of such large-scale screening be met? A scoping review of the literature was performed to ascertain what the genetic counselling needs of reproductive genetic carrier screening are, and what future research is needed. Four broad themes were identified in the existing literature: (1) The offer-when and in what context to offer screening; (2) Information-the importance of and what to include in education, and pre- and post-test counselling; (3) Who and how-who the genetic counselling is performed by and how; (4) Personalization-how do we find the balance between standardized and individualized approaches? Based on the existing literature, we present a set of recommendations for consideration in implementing population-scale reproductive genetic carrier screening as well as suggested areas for future research.
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Affiliation(s)
- Samantha Edwards
- Harry Perkins Institute of Medical Research and Centre for Medical Research, University of Western Australia, QEII Medical Centre, Nedlands, WA 6009, Australia
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Long Q, Feng Y, Chen F, Wang W, Ma M, Mao S. Association between serum zinc level and lipid profiles in children with spinal muscular atrophy. Front Nutr 2022; 9:960006. [PMID: 36046135 PMCID: PMC9420972 DOI: 10.3389/fnut.2022.960006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Accepted: 07/22/2022] [Indexed: 11/22/2022] Open
Abstract
Background and aims Children with spinal muscular atrophy (SMA) have a high rate of dyslipidaemia, which is a risk factor of vital importance for cardiovascular diseases in adulthood. Studies have demonstrated that the serum zinc level is associated with lipid profiles in the general population as well as in individuals diagnosed with obesity or diabetes. The purpose of this study was to evaluate the relationship between serum zinc level and lipid profiles in children with SMA. Methods This cross-sectional study was launched in a tertiary children's medical center in China and involved pediatric patients with SMA under the management of a multidisciplinary team of outpatient services from July 2019 to July 2021. Anthropometric information, general clinical data, serum zinc level, lipid profiles, and body composition data were collected. Multivariate analysis was used for a thorough inquiry on the association between the serum zinc level and lipid profiles. Results Among the 112 patients with SMA [median (IQR) age 5.54 years (2.75–8.29), 58.04% female], who fulfilled the inclusion criteria of the study, dyslipidaemia was detected in 60 patients (53.57%). Based on multivariable linear regression, serum zinc level was positively associated with high-density lipoprotein cholesterol (HDL-C; β = 1.63, 95% CI = 0.44–3.22) and apolipoprotein A1 (APO A1; β = 2.94, 95% CI = 0.03–5.85) levels, independently of age, sex, type, activity, percentage of body fat, and body mass index. As the serum zinc level increased by 10 μmol/L, the risk of low APO A1 levels decreased by 35% (OR = 0.65, 95% CI = 0.44–0.97) according to multivariable logistic regression analyses. Conclusion Serum zinc concentration was positively correlated with HDL-C and APO A1 levels among children with SMA. We suggest measures to correct the lower level of serum zinc to improve HDL-C and APO A1 levels.
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Affiliation(s)
- Qi Long
- Department of Clinical Nutrition, The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Yijie Feng
- Department of Neurology, The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Fei Chen
- Department of Clinical Nutrition, The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Wenqiao Wang
- Department of Clinical Nutrition, The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Ming Ma
- Department of Clinical Nutrition, The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
| | - Shanshan Mao
- Department of Neurology, The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China
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Xu Y, Song T, Wang X, Zheng J, Li Y, Guo F, Li Y, Guo Z, Dou Y, Wang Y, Zhao Y, Yang H. Copy number assessment of SMN1 based on real-time PCR with high-resolution melting: fast and highly reliable testing. Brain Dev 2022; 44:462-468. [PMID: 35414447 DOI: 10.1016/j.braindev.2022.03.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Revised: 03/24/2022] [Accepted: 03/29/2022] [Indexed: 10/18/2022]
Abstract
BACKGROUND Spinal muscular atrophy (SMA) is a neuromuscular disease mainly caused by the absence of both copies of the survival motor neuron 1 (SMN1) gene. Multiple regions recommended population-wide SMA screening to quantify the copy number of SMN1. SMN1 diagnostic assays for the simplified procedure, high sensitivity, and throughput continue to be needed. METHODS Real-time PCR with high-resolution melting for the quantifying of the SMN1 gene exon 7 copies and exon 8 copies were established and confirmed by multiplex ligation-dependent probe amplification (MLPA). The diagnosis of 2563 individuals, including SMA patients, suspected cases, and the general population, was tested by real-time PCR. The results were compared with the gold standard test MLPA. RESULTS In this study, the homozygous and heterozygous deletions were detected by real-time PCR with a high-resolution melting method with an incidence of 10.18% and 2.26%, respectively. In addition, the R-value distribution (P > 0.05) among 8 replicates and the coefficient of variation (CV < 0.003) suggested that the real-time PCR screening test had high reproducibility. High concordance was obtained between real-time PCR with high-resolution melting and MLPA. CONCLUSIONS The real-time PCR based on high-resolution melting provides a sensitive and high-throughput approach to large-scale SMA carrier screening with low cost and labor.
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Affiliation(s)
- Ying Xu
- Department of Obstetrics and Gynecology, Xijing Hospital, Fourth Military Medical University, Shannxi 710032, China
| | - Tingting Song
- Department of Obstetrics and Gynecology, Xijing Hospital, Fourth Military Medical University, Shannxi 710032, China
| | - Xiaozhou Wang
- Xi'an Tianlong Science and Technology CO., Ltd, China
| | - Jiao Zheng
- Department of Obstetrics and Gynecology, Xijing Hospital, Fourth Military Medical University, Shannxi 710032, China
| | - Yu Li
- Department of Obstetrics and Gynecology, Xijing Hospital, Fourth Military Medical University, Shannxi 710032, China
| | - Fenfen Guo
- Department of Obstetrics and Gynecology, Xijing Hospital, Fourth Military Medical University, Shannxi 710032, China
| | - Yuanfeng Li
- Department of Obstetrics and Gynecology, Xijing Hospital, Fourth Military Medical University, Shannxi 710032, China
| | - Zijian Guo
- Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, China
| | - Yaling Dou
- Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, China
| | - Yu Wang
- Xi'an Tianlong Science and Technology CO., Ltd, China
| | - Ye Zhao
- Xi'an Tianlong Science and Technology CO., Ltd, China.
| | - Hong Yang
- Department of Obstetrics and Gynecology, Xijing Hospital, Fourth Military Medical University, Shannxi 710032, China.
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Dos Santos M, Brighente SF, Massignan A, Tenório RB, Makariewicz LL, Moreira AL, Saute JA. Accuracy of muscle fasciculations for the diagnosis of later-onset spinal muscle atrophy. Neuromuscul Disord 2022; 32:763-768. [PMID: 35879189 DOI: 10.1016/j.nmd.2022.07.395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2021] [Revised: 06/29/2022] [Accepted: 07/10/2022] [Indexed: 10/17/2022]
Abstract
Diagnosis of later-onset spinal muscular atrophy (SMA) can be challenging. This study aimed to evaluate the diagnostic properties of the detection of muscle fasciculations for SMA diagnosis in adolescents and adults with proximal muscle weakness. A cross-sectional diagnostic accuracy study was performed, in which 10 subjects with SMA (5 with type II and 5 with type III) and 9 subjects with genetic muscle diseases were evaluated by physical examination, muscle ultrasound (MUS) and electromyography (EMG). Inter-rater reliability of MUS was higher than physical examination and in a sensitivity analysis of MUS, all SMA subjects and a single patient with genetic muscle disease presented fasciculations in at least 2 different muscle groups, resulting in a sensitivity of 1 (95% CI: 0.69 to 1) and a specificity of 0.89 (95% CI: 0.52 to 1) for SMA diagnosis. Forty-two percent of evaluated subjects did not agree to perform EMG, limiting this method results. Muscle ultrasound presented the best diagnostic accuracy and physical examination combined with MUS seemed to be a good strategy for screening adolescents and adults with proximal muscle weakness for SMA. These results might improve diagnostic guidelines for later-onset SMA, leading to earlier diagnosis, treatment and specific care.
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Affiliation(s)
- Mar Dos Santos
- Graduate Program in Medicine: Medical Sciences, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Samanta F Brighente
- Graduate Program in Medicine: Medical Sciences, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Angela Massignan
- Radiology Departament, Hospital Moinhos de Vento, Porto Alegre, Brazil
| | - Renata Barreto Tenório
- Hospital Pequeno Príncipe, Curitiba, Brazil; Graduate Program in Medicine: Internal Medicine, Universidade Federal do Paraná, Curitiba, Brazil
| | | | - Ana Lucila Moreira
- Department of Neurosurgery (Peripheral Nerve Surgery Unit), University of São Paulo - USP, São Paulo, Brazil
| | - Jonas Alex Saute
- Graduate Program in Medicine: Medical Sciences, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil; Medical Genetics Division, Hospital de Clínicas de Porto Alegre (HCPA), Porto Alegre, Brazil; Neurology Division, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil; Department of Internal Medicine, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.
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Tan C, Yan Y, Guo N, Wang F, Wang S, Zhu L, Wang Y, Ma Y, Guo Y. Single-Tube Multiplex Digital Polymerase Chain Reaction Assay for Molecular Diagnosis and Prediction of Severity of Spinal Muscular Atrophy. Anal Chem 2022; 94:3517-3525. [PMID: 35137581 DOI: 10.1021/acs.analchem.1c04403] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Spinal muscular atrophy (SMA) is an autosomal recessive neuromuscular disease characterized by the degeneration of motor neurons and progressive muscle atrophy. Accurate detection of SMN1 and SMN2 copy numbers is essential for SMA diagnosis, carrier screening, disease severity prediction, therapy, and prognosis. However, a method for SMN1 and SMN2 copy number determination that is simultaneously accurate, simple, rapid, multitargeted, and applicable to various samples has not previously been reported. Here, we developed a single-tube multiplex digital polymerase chain reaction (dPCR) assay for simultaneous determination of the copy numbers of SMN1 exons 7 and 8 and SMN2 exons 7 and 8. A total of 317 clinical samples, including peripheral blood, amniotic fluid, chorionic villus, buccal swabs, and dried blood spots, were collected to evaluate the performance of this dPCR-based assay. The test results were accurate for all the clinical samples. Our assay is accurate, rapid, easy to handle, and applicable to many types of samples and uses a small amount of DNA; it is a powerful tool for SMA molecular diagnosis, large-scale screening, and disease severity assessment.
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Affiliation(s)
- Chianru Tan
- Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing 100084, China
| | - Yousheng Yan
- Prenatal Diagnostic Center, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing 100026, China
| | - Na Guo
- TargetingOne Corporation, Beijing 100190, China
| | - Fang Wang
- TargetingOne Corporation, Beijing 100190, China
| | - Songtao Wang
- Department of Central Laboratory, Peking University First Hospital, Beijing 100034, China
| | | | - Yipeng Wang
- Prenatal Diagnostic Center, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing 100026, China
| | - Yinan Ma
- Department of Central Laboratory, Peking University First Hospital, Beijing 100034, China
| | - Yong Guo
- Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing 100084, China
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22
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Next generation sequencing is a highly reliable method to analyze exon 7 deletion of survival motor neuron 1 (SMN1) gene. Sci Rep 2022; 12:223. [PMID: 34997153 PMCID: PMC8741787 DOI: 10.1038/s41598-021-04325-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Accepted: 09/28/2021] [Indexed: 12/13/2022] Open
Abstract
Spinal muscular atrophy (SMA) is one of the most common and severe genetic diseases. SMA carrier screening is an effective way to identify couples at risk of having affected children. Next-generation sequencing (NGS)-based expanded carrier screening could detect SMN1 gene copy number without extra experiment and with high cost performance. However, its performance has not been fully evaluated. Here we conducted a systematic comparative study to evaluate the performance of three common methods. 478 samples were analyzed with multiplex ligation probe amplification (MLPA), real-time quantitative polymerase chain reaction (qPCR) and NGS, simultaneously. Taking MLPA-based results as the reference, for 0 copy, 1 copy and ≥ 2 copy SMN1 analysis with NGS, the sensitivity, specificity and precision were all 100%. Using qPCR method, the sensitivity was 100%, 97.52% and 94.30%, respectively; 98.63%, 95.48% and 100% for specificity; and 72.72%, 88.72% and 100% for precision. NGS repeatability was higher than that of qPCR. Moreover, among three methods, NGS had the lowest retest rate. Thus, NGS is a relatively more reliable method for SMN1 gene copy number detection. In expanded carrier screening, compared with the combination of multiple methods, NGS method could reduce the test cost and simplify the screening process.
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Mattar CNZ, Labude MK, Lee TN, Lai PS. Ethical considerations of preconception and prenatal gene modification in the embryo and fetus. Hum Reprod 2021; 36:3018-3027. [PMID: 34665851 DOI: 10.1093/humrep/deab222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 09/08/2021] [Indexed: 11/13/2022] Open
Abstract
The National Academies of Sciences and Medicine 2020 consensus statement advocates the reinstatement of research in preconception heritable human genome editing (HHGE), despite the ethical concerns that have been voiced about interventions in the germline, and outlines criteria for its eventual clinical application to address monogenic disorders. However, the statement does not give adequate consideration to alternative technologies. Importantly, it omits comparison to fetal gene therapy (FGT), which involves gene modification applied prenatally to the developing fetus and which is better researched and less ethically contentious. While both technologies are applicable to the same monogenic diseases causing significant prenatal or early childhood morbidity, the benefits and risks of HHGE are distinct from FGT though there are important overlaps. FGT has the current advantage of a wealth of robust preclinical data, while HHGE is nascent technology and its feasibility for specific diseases still requires scientific proof. The ethical concerns surrounding each are unique and deserving of further discussion, as there are compelling arguments supporting research and eventual clinical translation of both technologies. In this Opinion, we consider HHGE and FGT through technical and ethical lenses, applying common ethical principles to provide a sense of their feasibility and acceptability. Currently, FGT is in a more advanced position for clinical translation and may be less ethically contentious than HHGE, so it deserves to be considered as an alternative therapy in further discussions on HHGE implementation.
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Affiliation(s)
- Citra Nurfarah Zaini Mattar
- Experimental Fetal Medicine Group, Department of Obstetrics and Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.,Department of Obstetrics and Gynaecology, National University Health System, Singapore, Singapore
| | - Markus Klaus Labude
- Science, Health and Policy-Relevant Ethics in Singapore (SHAPES) Initiative, Centre for Biomedical Ethics, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Timothy Nicholas Lee
- Science, Health and Policy-Relevant Ethics in Singapore (SHAPES) Initiative, Centre for Biomedical Ethics, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Poh San Lai
- Department of Paediatrics, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
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Systematic review of outcomes in studies of reproductive genetic carrier screening: Towards development of a core outcome set. Genet Med 2021; 24:1-14. [PMID: 34906455 DOI: 10.1016/j.gim.2021.08.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 06/09/2021] [Accepted: 09/10/2021] [Indexed: 01/08/2023] Open
Abstract
PURPOSE Current practice recommendations support the widespread implementation of reproductive genetic carrier screening (RGCS). These consensus-based recommendations highlight a research gap, with findings from current studies being insufficient to meet the standard required for more rigorous evidence-based recommendations. This systematic review assessed methodological aspects of studies on RGCS to inform the need for a core outcome set. METHODS We conducted a systematic search to identify peer-reviewed published studies offering population-based RGCS. Study designs, outcomes, and measurement methods were extracted. A narrative synthesis was conducting using an existing outcome taxonomy and criteria used in the evaluation of genetic screening programs as frameworks. RESULTS Sixty-five publications were included. We extracted 120 outcomes representing 24 outcome domains. Heterogeneity in outcome selection, measurement methods and time points of assessment was extensive. Quality appraisal raised concerns for bias. We found that reported outcomes had limited applicability to criteria used to evaluate genetic screening programs. CONCLUSION Despite a large body of literature, diverse approaches to research have limited the conclusions that can be cumulatively drawn from this body of evidence. Consensus regarding meaningful outcomes for evaluation of RGCS would be a valuable first step in working towards evidence-based practice recommendations, supporting the development of a core outcome set.
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Butchbach MER. Genomic Variability in the Survival Motor Neuron Genes ( SMN1 and SMN2): Implications for Spinal Muscular Atrophy Phenotype and Therapeutics Development. Int J Mol Sci 2021; 22:ijms22157896. [PMID: 34360669 PMCID: PMC8348669 DOI: 10.3390/ijms22157896] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 07/14/2021] [Accepted: 07/21/2021] [Indexed: 02/07/2023] Open
Abstract
Spinal muscular atrophy (SMA) is a leading genetic cause of infant death worldwide that is characterized by loss of spinal motor neurons leading to muscle weakness and atrophy. SMA results from the loss of survival motor neuron 1 (SMN1) gene but retention of its paralog SMN2. The copy numbers of SMN1 and SMN2 are variable within the human population with SMN2 copy number inversely correlating with SMA severity. Current therapeutic options for SMA focus on increasing SMN2 expression and alternative splicing so as to increase the amount of SMN protein. Recent work has demonstrated that not all SMN2, or SMN1, genes are equivalent and there is a high degree of genomic heterogeneity with respect to the SMN genes. Because SMA is now an actionable disease with SMN2 being the primary target, it is imperative to have a comprehensive understanding of this genomic heterogeneity with respect to hybrid SMN1–SMN2 genes generated by gene conversion events as well as partial deletions of the SMN genes. This review will describe this genetic heterogeneity in SMA and its impact on disease phenotype as well as therapeutic efficacy.
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Affiliation(s)
- Matthew E. R. Butchbach
- Center for Applied Clinical Genomics, Nemours Children’s Health Delaware, Wilmington, DE 19803, USA;
- Center for Pediatric Research, Nemours Children’s Health Delaware, Wilmington, DE 19803, USA
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA
- Department of Pediatrics, Thomas Jefferson University, Philadelphia, PA 19107, USA
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Spinal Muscular Atrophy: Inheritance, Screening, and Counseling for the Obstetric Provider. Obstet Gynecol Surv 2021; 76:166-169. [PMID: 33783545 DOI: 10.1097/ogx.0000000000000870] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Importance Spinal muscular atrophy (SMA) confers significant risk of neonatal and infant morbidity and mortality. Screening women during or before pregnancy for carrier status of SMA presents an opportunity to identify pregnancies at risk for this potentially devastating condition. Objective The objective of this review is to describe the different forms of SMA and their inheritance. In addition, this review guides obstetric providers in interpreting results of carrier screening. Evidence Acquisition A MEDLINE search of "prenatal genetic testing," "spinal muscular atrophy," and "inheritance of spinal muscular atrophy" in the review was performed. Results The evidence cited in this review includes 4 medical society committee opinions and 14 additional peer-reviewed journal articles that were original research or expert opinion summaries. Conclusions and Relevance Spinal muscular atrophy is a severe, heterogeneous neurodegenerative disorder. The American College of Obstetricians and Gynecologists recommends that obstetricians offer carrier screening for SMA to all pregnant women. Given the different types and inheritance of SMA, understanding of the disease and interpreting carrier screening results is of paramount importance to the prenatal care provider.
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Ou SF, Ho CS, Lee WT, Lin KL, Jones CC, Jong YJ. Natural history in spinal muscular atrophy Type I in Taiwanese population: A longitudinal study. Brain Dev 2021; 43:127-134. [PMID: 32878721 DOI: 10.1016/j.braindev.2020.07.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Revised: 06/30/2020] [Accepted: 07/16/2020] [Indexed: 02/02/2023]
Abstract
INTRODUCTION Spinal muscular atrophy (SMA) is caused by a defect in the survival motor neuron 1 (SMN1) gene. The Cooperative Study of the natural history of SMA Type I in Taiwan is a retrospective, longitudinal, observational study that helps in further understanding SMA disease progression in patients who have not received disease-modifying therapeutic interventions. METHODS Case report forms were used to collect demographics; genetic confirmation; SMN2 copy number; treatment patterns; and clinical outcomes including ventilator use, endotracheal tube intubation, tracheostomy, gastrostomy, complications, and survival. RESULTS A total of 111 patients with SMA Type I were identified over the study period (1979-2015). Mean (median) age of onset and age at confirmed diagnosis were 1.3 (0.8) and 4.9 (4.4) months, respectively. SMN1 deletion/mutation was documented in 70 patients and SMN2 copy number in 32 (2 copies, n = 20; 3 copies, n = 12). At 240 months, survival probability for patients born during 1995-2015 versus 1979-1994 was significantly longer (p = 0.0057). Patients with 3 SMN2 copies showed substantially longer 240-month survival versus patients with 2 SMN2 copies. Over the 36-year period, mean (median) age at death was 31.9 (8.8) months. As of December 2015, 95 patients had died, 13 were alive, and 3 were lost to follow-up. The use of supportive measures (tracheostomy and gastrostomy) was associated with improved survival. CONCLUSIONS These data describe the short survival of patients with SMA Type I in Taiwan in the pretreatment era, emphasizing the positive impact of supportive measures on survival.
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Affiliation(s)
- Shan-Fu Ou
- Department of Pediatrics, Antai Medical Care Cooperation Antai Tian-Sheng Memorial Hospital, Pingtung, Taiwan
| | - Che-Sheng Ho
- Division of Pediatric Neurology, Department of Pediatrics, MacKay Children's Hospital, Taipei, Taiwan; Department of Medicine, MacKay Medical College, New Taipei, Taiwan
| | - Wang-Tso Lee
- Department of Pediatrics, National Taiwan University Hospital, and National Taiwan University, College of Medicine, Taipei, Taiwan
| | - Kuang-Lin Lin
- Division of Pediatric Neurology, Chang Gung Children's Hospital, Chang Gung Memorial Hospital, Chang Gung University, College of Medicine, Taoyuan, Taiwan
| | - Cynthia C Jones
- Department of Epidemiology, Global Analytics and Data Sciences, Biogen, Cambridge, MA, USA
| | - Yuh-Jyh Jong
- Graduate Institute of Clinical Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Departments of Pediatrics and Laboratory Medicine, and Translational Research Center of Neuromuscular Diseases, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan; College of Biological Science and Technology, National Chiao Tung University, Hsinchu, Taiwan.
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Park JE, Yun SA, Roh EY, Yoon JH, Shin S, Ki CS. Carrier Frequency of Spinal Muscular Atrophy in a Large-scale Korean Population. Ann Lab Med 2020; 40:326-330. [PMID: 32067433 PMCID: PMC7054693 DOI: 10.3343/alm.2020.40.4.326] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Revised: 09/29/2019] [Accepted: 01/16/2020] [Indexed: 12/13/2022] Open
Abstract
Spinal muscular atrophy (SMA) is an autosomal recessive disease characterized by progressive proximal muscle weakness and atrophy. Given the recent introduction of gene therapies, knowledge of the SMA carrier frequency in various populations has become important for developing screening programs for this disease. In total, 1,581 anonymous DNA samples from an umbilical cord blood bank were tested for SMN1 and SMN2 gene copies using a multiplex ligation-dependent probe amplification assay. Twenty-nine of the 1,581 newborns [1.83%; 95% confidence interval (CI), 1.25–2.66%] were SMA carriers with one copy of SMN1, and no homozygous SMN1 deletion was detected. The carrier frequency in this population was estimated to be 1,834 per 100,000 (95% CI, 1,254–2,659) or 1 in 55 (95% CI, 1/79–1/38). Our data indicate that SMA carriers are not uncommon in the Korean population and may serve as a reference for designing a population screening program in Korea.
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Affiliation(s)
- Jong Eun Park
- Department of Laboratory Medicine, Hanyang University Guri Hospital, Hanyang University College of Medicine, Guri, Korea
| | - Sun Ae Yun
- Center for Clinical Medicine, Samsung Biomedical Research Institute, Samsung Medical Center, Seoul, Korea
| | - Eun Youn Roh
- Department of Laboratory Medicine, Boramae Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - Jong Hyun Yoon
- Department of Laboratory Medicine, Boramae Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - Sue Shin
- Department of Laboratory Medicine, Boramae Hospital, Seoul National University College of Medicine, Seoul, Korea.
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Wang KC, Fang CY, Chang CC, Chiang CK, Chen YW. A rapid molecular diagnostic method for spinal muscular atrophy. J Neurogenet 2020; 35:29-32. [PMID: 33332175 DOI: 10.1080/01677063.2020.1853721] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Spinal muscular atrophy (SMA) is a common autosomal recessive disorder which has been considered as the second common cause of infant death, with an estimated prevalence of 1 in 10,000 live births. The disorder is caused by survival motor neuron 1 gene (SMN1) deficiency leading to limb weakness, difficult swallowing and abnormal breathing. Here, a fast and accurate method for SMA detection has been developed. Genomic DNA sample collected from whole blood, amniotic fluid, or dried blood spots can be analysed by using the Clarity™ Digital PCR (dPCR) System for determining the copy numbers of SMN1 and SMN2 genes. Two hundred and fourteen clinical samples determined by qPCR-based method were enrolled and used to establish the cut-off ranges for unaffected individual, SMA carrier and SMA patient categories. After setting the cut-off range for each group, 12 samples were analyzed by both dPCR-based method and MLPA (multiplex ligation-dependent probe amplification), the current testing golden standard for SMA, and 100% concordant results between the two testing methods were performed. CSB SMA Detection Kit combined with dPCR platform provides a robust and precise approach to distinguish unaffected individuals, SMA carrier and SMA patients. This rapid molecular diagnostic method can be adapted to pre-pregnancy eugenics inspection, prenatal testing as well as newborns screening and help physicians or genetic counselors to improve population SMA incidence.
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Affiliation(s)
- Kai-Chen Wang
- Cheng-Hsin General Hospital, Taipei, Taiwan.,School of Medicine, National Yang Ming University, Taipei, Taiwan
| | | | | | | | - Yi-Wen Chen
- Cold Spring Biotech Corp, New Taipei City, Taiwan
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Lopez-Lopez D, Loucera C, Carmona R, Aquino V, Salgado J, Pasalodos S, Miranda M, Alonso Á, Dopazo J. SMN1 copy-number and sequence variant analysis from next-generation sequencing data. Hum Mutat 2020; 41:2073-2077. [PMID: 33058415 PMCID: PMC7756735 DOI: 10.1002/humu.24120] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2020] [Revised: 08/17/2020] [Accepted: 09/17/2020] [Indexed: 12/31/2022]
Abstract
Spinal muscular atrophy (SMA) is a severe neuromuscular autosomal recessive disorder affecting 1/10,000 live births. Most SMA patients present homozygous deletion of SMN1, while the vast majority of SMA carriers present only a single SMN1 copy. The sequence similarity between SMN1 and SMN2, and the complexity of the SMN locus makes the estimation of the SMN1 copy-number by next-generation sequencing (NGS) very difficult. Here, we present SMAca, the first python tool to detect SMA carriers and estimate the absolute SMN1 copy-number using NGS data. Moreover, SMAca takes advantage of the knowledge of certain variants specific to SMN1 duplication to also identify silent carriers. This tool has been validated with a cohort of 326 samples from the Navarra 1000 Genomes Project (NAGEN1000). SMAca was developed with a focus on execution speed and easy installation. This combination makes it especially suitable to be integrated into production NGS pipelines. Source code and documentation are available at https://www.github.com/babelomics/SMAca.
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Affiliation(s)
- Daniel Lopez-Lopez
- Clinical Bioinformatics Area, Fundación Progreso y Salud (FPS), CDCA, Hospital Virgen del Rocio, Sevilla, Spain.,Computational Systems Medicine, Institute of Biomedicine of Seville (IBIS), Hospital Virgen del Rocio, Sevilla, Spain
| | - Carlos Loucera
- Clinical Bioinformatics Area, Fundación Progreso y Salud (FPS), CDCA, Hospital Virgen del Rocio, Sevilla, Spain.,Computational Systems Medicine, Institute of Biomedicine of Seville (IBIS), Hospital Virgen del Rocio, Sevilla, Spain
| | - Rosario Carmona
- Clinical Bioinformatics Area, Fundación Progreso y Salud (FPS), CDCA, Hospital Virgen del Rocio, Sevilla, Spain
| | - Virginia Aquino
- Clinical Bioinformatics Area, Fundación Progreso y Salud (FPS), CDCA, Hospital Virgen del Rocio, Sevilla, Spain
| | - Josefa Salgado
- Genomic Medicine, Navarrabiomed, Complejo Hospitalario de Navarra (CHN)-Universidad Pública de Navarra (UPNA), IDISNA, Pamplona, Spain
| | - Sara Pasalodos
- Genomic Medicine, Navarrabiomed, Complejo Hospitalario de Navarra (CHN)-Universidad Pública de Navarra (UPNA), IDISNA, Pamplona, Spain
| | - María Miranda
- Genomic Medicine, Navarrabiomed, Complejo Hospitalario de Navarra (CHN)-Universidad Pública de Navarra (UPNA), IDISNA, Pamplona, Spain
| | - Ángel Alonso
- Genomic Medicine, Navarrabiomed, Complejo Hospitalario de Navarra (CHN)-Universidad Pública de Navarra (UPNA), IDISNA, Pamplona, Spain
| | - Joaquín Dopazo
- Clinical Bioinformatics Area, Fundación Progreso y Salud (FPS), CDCA, Hospital Virgen del Rocio, Sevilla, Spain.,Computational Systems Medicine, Institute of Biomedicine of Seville (IBIS), Hospital Virgen del Rocio, Sevilla, Spain.,Bioinformatics in Rare Diseases (BiER), Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), FPS, Hospital Virgen del Rocío, Sevilla, Spain.,FPS/ELIXIR-es, Hospital Virgen del Rocío, Sevilla, Spain
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31
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CMAP changes upon symptom onset and during treatment in spinal muscular atrophy patients: lessons learned from newborn screening. Genet Med 2020; 23:415-420. [PMID: 33033402 DOI: 10.1038/s41436-020-00987-w] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 09/20/2020] [Accepted: 09/21/2020] [Indexed: 02/04/2023] Open
Abstract
PURPOSE Early identification and treatment of spinal muscular atrophy (SMA) are crucial but difficult. In this study, we aimed to assess the significance of compound motor action potential (CMAP) amplitude in patients identified through a newborn screening program. METHODS We initiated a large-scale population newborn screening program for SMA in Taiwan in 2014. Patients had access to treatment through clinical trials or expanded use programs. Symptomatic patients were evaluated regularly, including CMAP exams. RESULTS Among 364,000 screened newborns, 21 were diagnosed with SMA. The incidence of SMA was around 1 in 17,000 live births, and 70% developed SMA type 1. All infants with two SMN2 copies became symptomatic before the age of 1 month. CMAP amplitudes of 12 newborns were available, including 6 who were subsequently treated with nusinersen. We found that a rapid decrease of CMAP amplitude was an early predictor of symptom onset. Pretreatment CMAP and rapid increment of post-treatment CMAP could predict better treatment outcomes. CONCLUSION This study prospectively demonstrated the incidence of SMA and its types. Our results imply the importance of pretreatment CMAP amplitude and rapid reversal of post-treatment CMAP amplitude with regard to disease presentation and also treatment outcomes.
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Zhao S, Wang W, Wang Y, Han R, Fan C, Ni P, Guo F, Zeng F, Yang Q, Yang Y, Sun Y, Zhang X, Chen Y, Zhu B, Cai W, Chen S, Cai R, Guo X, Zhang C, Zhou Y, Huang S, Liu Y, Chen B, Yan S, Chen Y, Ding H, Shang X, Xu X, Sun J, Peng Z. NGS-based spinal muscular atrophy carrier screening of 10,585 diverse couples in China: a pan-ethnic study. Eur J Hum Genet 2020; 29:194-204. [PMID: 32884118 DOI: 10.1038/s41431-020-00714-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 06/09/2020] [Accepted: 08/04/2020] [Indexed: 11/09/2022] Open
Abstract
In this study, we performed a spinal muscular atrophy carrier screening investigation with NGS-based method. First, the validation for NGS-based method was implemented in 2255 samples using real-time PCR. The concordance between the NGS-based method and real-time PCR for the detection of SMA carrier and patient were up to 100%. Then, we applied this NGS-based method in 10,585 self-reported normal couples (34 Chinese ethnic groups from 5 provinces in South China) for SMA carrier screening. The overall carrier frequency was 1 in 73.8 (1.4%). It varied substantially between ethnic groups, highest in Dai ethnicity (4.3%), and no significant difference was found between five provinces. One couple was detected as carriers with an elevated risk of having an SMA affected baby. The distribution of SMN1:SMN2 genotype was also revealed in this study. Among the individuals with normal phenotype, the exon 7 copy-number ratio of SMN1 to SMN2 proved the gene conversion between them. With NGS-based method, we investigated SMA carrier status in Chinese population for the first time, and our results demonstrated that it is a promising alternative for SMA carrier screening and could provide data support and reference for future clinical application.
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Affiliation(s)
- Sumin Zhao
- Tianjin Medical Laboratory, BGI-Tianjin, BGI-Shenzhen, 300308, Tianjin, China.,Binhai Genomics Institute, BGI-Tianjin, BGI-Shenzhen, 300308, Tianjin, China
| | - Wanyang Wang
- Tianjin Medical Laboratory, BGI-Tianjin, BGI-Shenzhen, 300308, Tianjin, China.,Binhai Genomics Institute, BGI-Tianjin, BGI-Shenzhen, 300308, Tianjin, China
| | - Yaoshen Wang
- Tianjin Medical Laboratory, BGI-Tianjin, BGI-Shenzhen, 300308, Tianjin, China.,Binhai Genomics Institute, BGI-Tianjin, BGI-Shenzhen, 300308, Tianjin, China
| | - Rui Han
- Tianjin Medical Laboratory, BGI-Tianjin, BGI-Shenzhen, 300308, Tianjin, China.,Binhai Genomics Institute, BGI-Tianjin, BGI-Shenzhen, 300308, Tianjin, China
| | - Chunna Fan
- Tianjin Medical Laboratory, BGI-Tianjin, BGI-Shenzhen, 300308, Tianjin, China.,Binhai Genomics Institute, BGI-Tianjin, BGI-Shenzhen, 300308, Tianjin, China
| | - Peixiang Ni
- Tianjin Medical Laboratory, BGI-Tianjin, BGI-Shenzhen, 300308, Tianjin, China.,Binhai Genomics Institute, BGI-Tianjin, BGI-Shenzhen, 300308, Tianjin, China
| | - Fengyu Guo
- Tianjin Medical Laboratory, BGI-Tianjin, BGI-Shenzhen, 300308, Tianjin, China.,Binhai Genomics Institute, BGI-Tianjin, BGI-Shenzhen, 300308, Tianjin, China
| | - Fanwei Zeng
- BGI Genomics, BGI-Shenzhen, 518083, Shenzhen, China
| | - Qiaona Yang
- BGI Genomics, BGI-Shenzhen, 518083, Shenzhen, China
| | - Yun Yang
- BGI Genomics, BGI-Shenzhen, 518083, Shenzhen, China
| | - Yan Sun
- BGI Genomics, BGI-Shenzhen, 518083, Shenzhen, China.,James D. Watson Institute of Genome Science, 310008, Hangzhou, China
| | - Xinhua Zhang
- Department of Hematology, 303rd Hospital of the People's Liberation Army, Nanning, Guangxi, China
| | - Yan Chen
- The Second Department of Pediatrics, Affiliated Hospital of Zunyi Medical College, Zunyi, Guizhou, China
| | - Baosheng Zhu
- Nation Health and Family Planning Commission Key Laboratory For Preconception and Health Birth in Western China, The First People's Hospital of Yunnan Province, Kunming University of Science and Technology, Kunming, China
| | - Wangwei Cai
- Department of Biochemistry and Molecular Biology, Hainan Medical College, Haikou, Hainan, China
| | - Shaoke Chen
- Department of Genetic and Metabolic Laboratory, Guangxi Zhuang Autonomous Region Women and Children Health Care Hospital, Nanning, Guangxi, China
| | - Ren Cai
- Department of Medical Genetics, Liuzhou Municipal Maternity and Child Healthcare Hospital, Liuzhou, Guangxi, China
| | - Xiaoling Guo
- Maternity and Child Health Care Hospital of Foshan City, Foshan, Guangdong, China
| | - Chonglin Zhang
- Guilin Women and Children Health Care Hospital, Guilin, Guangxi, China
| | - Yuqiu Zhou
- Department of Clinical Laboratory, Zhuhai Municipal Maternal and Child Healthcare Hospital, Zhuhai Institute of Medical Genetics, Zhuhai, Guangdong, China
| | - Shuodan Huang
- Maternal and Child Health Hospital in Meizhou, Meizhou, Guangdong, China
| | - Yanhui Liu
- Department of Prenatal Diagnosis Center, Dong Guan Maternal and Child Health Hospital, Dongguan, Guangdong, China
| | - Biyan Chen
- Baise Women and Children Care Hospital, Baise, Guangxi, China
| | - Shanhuo Yan
- Genetic Laboratory, Qinzhou Maternal and Child Health Hospital, Qingzhou, Guangxi, China
| | - Yajun Chen
- Women and Children's Health Hospital of Shaoguan, Shaoguan, Guangdong, China
| | - Hongmei Ding
- Department of Gynecology and Obstetrics, The People's Hospital of Yunfu City, Yunfu, Guangdong, China
| | - Xuan Shang
- Department of Medical Genetics, School of Basic Medical Sciences, Southern Medical University, Guangzhou, 510515, Guangdong, China
| | - Xiangmin Xu
- Department of Medical Genetics, School of Basic Medical Sciences, Southern Medical University, Guangzhou, 510515, Guangdong, China
| | - Jun Sun
- Tianjin Medical Laboratory, BGI-Tianjin, BGI-Shenzhen, 300308, Tianjin, China. .,Binhai Genomics Institute, BGI-Tianjin, BGI-Shenzhen, 300308, Tianjin, China.
| | - Zhiyu Peng
- BGI Genomics, BGI-Shenzhen, 518083, Shenzhen, China.
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Pan J, Zhang C, Teng Y, Zeng S, Chen S, Liang D, Li Z, Wu L. Detection of Spinal Muscular Atrophy Using a Duplexed Real-Time PCR Approach With Locked Nucleic Acid-Modified Primers. Ann Lab Med 2020; 41:101-107. [PMID: 32829585 PMCID: PMC7443528 DOI: 10.3343/alm.2021.41.1.101] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 03/24/2020] [Accepted: 07/17/2020] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Spinal muscular atrophy (SMA) is an autosomal recessive neuromuscular disorder mainly caused by homozygous deletions that include exon 7 of the survival motor neuron 1 (SMN1) gene. A nearby paralog gene, SMN2, obstructs the specific detection of SMN1. We optimized a duplexed real-time PCR approach using locked nucleic acid (LNA)-modified primers to specifically detect SMN1. METHODS An LNA-modified primer pair with 3' ends targeting SMN1 specific sites c.835-44g and c.840C was designed, and its specificity was examined by real-time PCR and Sanger Sequencing. A duplexed real-time PCR approach for amplifying SMN1 and control gene albumin (ALB) was developed. A randomized double-blind trial with 97 fresh peripheral blood samples and 25 dried blood spots (DBS) was conducted to evaluate the clinical efficacy of the duplexed approach. This new approach was then used to screen 753 newborn DBS. RESULTS The LNA-modified primers exhibited enhanced specificity and 6.8% increased efficiency for SMN1 amplification, compared with conventional primers. After stabilizing the SMN1 test by optimizing the duplexed real-time PCR approach, a clinical trial validated that the sensitivity and specificity of our new approach for detecting SMA patients and carriers was 100%. Using this new approach, 15 of the screened 753 newborns were identified as carriers via DBS, while the rest were identified as normal individuals. These data reveal a carrier rate of 1.99% in Hunan province, South Central China. CONCLUSIONS We have developed a novel, specific SMN1 detection approach utilizing real-time PCR with LNA-modified primers, which could be applied to both prenatal carrier and newborn screening.
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Affiliation(s)
- Jianyan Pan
- Center for Medical Genetics & Hunan Key Laboratory of Medical Genetics, School of Life Sciences, Central South University, Changsha, Hunan, China
| | - Chunhua Zhang
- Center for Medical Genetics & Hunan Key Laboratory of Medical Genetics, School of Life Sciences, Central South University, Changsha, Hunan, China
| | - Yanling Teng
- Laboratory of Molecular Genetics, Hunan Jiahui Genetics Hospital, Changsha, Hunan, China
| | - Sijing Zeng
- Center for Medical Genetics & Hunan Key Laboratory of Medical Genetics, School of Life Sciences, Central South University, Changsha, Hunan, China
| | - Siyi Chen
- Center for Medical Genetics & Hunan Key Laboratory of Medical Genetics, School of Life Sciences, Central South University, Changsha, Hunan, China
| | - Desheng Liang
- Center for Medical Genetics & Hunan Key Laboratory of Medical Genetics, School of Life Sciences, Central South University, Changsha, Hunan, China
| | - Zhuo Li
- Center for Medical Genetics & Hunan Key Laboratory of Medical Genetics, School of Life Sciences, Central South University, Changsha, Hunan, China
| | - Lingqian Wu
- Center for Medical Genetics & Hunan Key Laboratory of Medical Genetics, School of Life Sciences, Central South University, Changsha, Hunan, China
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Abstract
Spinal muscular atrophy (SMA) is an autosomal recessive neuromuscular disease caused by deletions or mutations in the survival motor neuron (SMN1) gene. SMA is characterized by loss of lower motor neurons (anterior horn cells) in the spinal cord and brainstem nuclei, leading to progressive symmetrical muscle weakness and atrophy. It affects approximately 1 in 6,000 to 1 in 10,000 individuals and is the most common inherited cause of childhood mortality, but this may soon change given recent developments. In December 2016, nusinersen, an antisense oligonucleotide drug, was approved by the United States Food and Drug Administration for the treatment of SMA, and in July 2018, SMA was added to the recommended uniform screening panel, a list of conditions that all states are encouraged to include in their newborn screening (NBS) panels. In this review, we begin with a brief clinical history of the diagnosis of SMA, discuss the current SMA clinical classification system, describe the current treatment, and discuss evolving treatment guidelines. We then discuss the path to include SMA in NBS programs as well as the controversies it engenders because the variability in age at symptom onset means early identification of asymptomatic patients who will not require therapy for years or decades. We also consider alternate population screening opportunities. Next, we consider experimental treatments. We conclude by supporting NBS for SMA with the caveat that a long-term follow-up registry is ethically essential to ensure that the benefits outweigh the harms for all screened infants, including those with milder and/or later-onset forms of SMA.
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Affiliation(s)
- Lainie Friedman Ross
- Departments of Pediatrics, Medicine, Surgery and the College; MacLean Center for Clinical Medical Ethics, University of Chicago, Chicago, IL
| | - Jennifer M Kwon
- Department of Neurology, University of Wisconsin School of Medicine and Public Health, Madison, WI
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35
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Zhang J, Wang Y, Ma D, Sun Y, Li Y, Yang P, Luo C, Jiang T, Hu P, Xu Z. Carrier Screening and Prenatal Diagnosis for Spinal Muscular Atrophy in 13,069 Chinese Pregnant Women. J Mol Diagn 2020; 22:817-822. [PMID: 32205292 DOI: 10.1016/j.jmoldx.2020.03.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 02/17/2020] [Accepted: 03/11/2020] [Indexed: 10/24/2022] Open
Abstract
Spinal muscular atrophy (SMA) is a relatively common, life-shortening, autosomal recessive neuromuscular disease. The carrier frequency of SMA ranges from approximately 0.98% to 2.02%, depending on ethnicity. The American College of Medical Genetics has therefore recommended population screening for SMA carrier status, regardless of race or ethnicity. We performed the largest-scale carrier screening for SMA carriers in mainland China. Carrier screening was offered to 36,470 pregnant women between July 2017 and June 2019, of whom 13,069 women accepted the screening program [35.83%; 95% credibility interval (CI), 35.34%-36.33%]. Copy numbers of exons 7 and 8 in the SMN1 gene were detected by real-time quantitative PCR, and the results were confirmed by multiplex ligation-dependent probe amplification. A total of 231 women were identified as carriers (1.77%; 95% CI, 1.56%-2.01%), indicating a carrier prevalence of approximately 1:56 in the population. After detailed genetic counseling, 207 paternal partners were recalled and tested. Both partners were carriers in 10 couples, of whom prenatal diagnosis was implemented in seven, and one fetus was diagnosed with SMA. Carrier screening could provide couples with informed reproductive choices. Our workflow and experience of carrier screening may facilitate the popularization of SMA carrier screening in mainland China.
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Affiliation(s)
- Jingjing Zhang
- Department of Prenatal Diagnosis, Nanjing Maternity and Child Health Care Hospital, Women's Hospital of Nanjing Medical University, Nanjing, People's Republic of China
| | - Yuguo Wang
- Department of Prenatal Diagnosis, Nanjing Maternity and Child Health Care Hospital, Women's Hospital of Nanjing Medical University, Nanjing, People's Republic of China
| | - Dingyuan Ma
- Department of Prenatal Diagnosis, Nanjing Maternity and Child Health Care Hospital, Women's Hospital of Nanjing Medical University, Nanjing, People's Republic of China
| | - Yun Sun
- Department of Prenatal Diagnosis, Nanjing Maternity and Child Health Care Hospital, Women's Hospital of Nanjing Medical University, Nanjing, People's Republic of China
| | - Yahong Li
- Department of Prenatal Diagnosis, Nanjing Maternity and Child Health Care Hospital, Women's Hospital of Nanjing Medical University, Nanjing, People's Republic of China
| | - Peiying Yang
- Department of Prenatal Diagnosis, Nanjing Maternity and Child Health Care Hospital, Women's Hospital of Nanjing Medical University, Nanjing, People's Republic of China
| | - Chunyu Luo
- Department of Prenatal Diagnosis, Nanjing Maternity and Child Health Care Hospital, Women's Hospital of Nanjing Medical University, Nanjing, People's Republic of China
| | - Tao Jiang
- Department of Prenatal Diagnosis, Nanjing Maternity and Child Health Care Hospital, Women's Hospital of Nanjing Medical University, Nanjing, People's Republic of China
| | - Ping Hu
- Department of Prenatal Diagnosis, Nanjing Maternity and Child Health Care Hospital, Women's Hospital of Nanjing Medical University, Nanjing, People's Republic of China.
| | - Zhengfeng Xu
- Department of Prenatal Diagnosis, Nanjing Maternity and Child Health Care Hospital, Women's Hospital of Nanjing Medical University, Nanjing, People's Republic of China
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Zhang Y, He J, Zhang Y, Li L, Tang X, Wang L, Guo J, Jin C, Tighe S, Zhang Y, Zhu Y, Zhu B. The analysis of the association between the copy numbers of survival motor neuron gene 2 and neuronal apoptosis inhibitory protein genes and the clinical phenotypes in 40 patients with spinal muscular atrophy: Observational study. Medicine (Baltimore) 2020; 99:e18809. [PMID: 32011487 PMCID: PMC7220227 DOI: 10.1097/md.0000000000018809] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
In this article, the correlation between the copy number of survival motor neuron 2 (SMN2) gene, neuronal apoptosis inhibitory protein (NAIP), and the phenotype of spinal muscular atrophy patients were analyzed.Forty patients with spinal muscular atrophy (SMA) were included in the study at the Department of Medical Genetics of the First People's Hospital and the Department of Neurology of the Second People's Hospital in Yunnan Province from January 2012 to September 2018. Multiplex ligation-dependent probe amplification assay was performed to determine the copy numbers of SMN2 and NAIP genes. Statistical analysis was performed to determine the correlation between copy numbers of the SMN2 and NAIP genes and the clinical phenotypes of SMA.Our results show that among the 40 SMA patients, there were 13 type I cases, 16 type II cases and 11 type III cases. A total of 37 patients possessed a homozygous deletion of SMN1 exons 7 and 8, while the other 3 SMA patients possessed a single copy of SMN1 exon 8. There was no correlation between SMA subtypes and the deletion types of SMN1 exon 7 and 8 (P = .611). The percentage of 2, 3, and 4 copies of SMN2 exon 7 was 25.0%, 62.5%, and 12.5%, respectively. The percentage of 0, 1, and 2 copies of NAIP exon 5 was 10%, 57.5%, and 32.5%, respectively. The distributions of SMN2 and NAIP copy numbers among various SMA types were significantly different (all P < .05). Five combined SMN1-SMN2-NAIP genotypes were detected, of which 0-3-1 genotype had the highest proportion than the others, accounting for 42.5%. The copy number of SMN2 and NAIP gene had synergistic effect on SMA phenotype. The combined SMN1-SMN2-NAIP genotypes with fewer copies were associated with earlier onset age, higher mortality, and smaller average age at death in SMA patients.Therefore, we conclude that the copy number variance of SMN2 and NAIP is correlated with the SMA phenotype. Analysis of the copy number structure of the SMN1-SMN2-NAIP gene is helpful for SMA typing, disease prognosis prediction, and genetic counseling.
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Affiliation(s)
- Yinhong Zhang
- Department of Medical Genetics, The First People's Hospital of Yunnan Province, The Affiliated Hospital of Kunming University of Science and Technology
- Faculty of Life Science and Biotechnology, Kunming University of Science and Technology
| | - Jing He
- Department of Medical Genetics, The First People's Hospital of Yunnan Province, The Affiliated Hospital of Kunming University of Science and Technology
| | - Yunqian Zhang
- Department of Neurology, The Second People's Hospital of Yunnan Province
| | - Li Li
- Faculty of Life Science and Biotechnology, Kunming University of Science and Technology
- Department of Pediatrics, The First People's Hospital of Yunnan Province, Kunming, Yunnan, China
| | - Xinhua Tang
- Department of Medical Genetics, The First People's Hospital of Yunnan Province, The Affiliated Hospital of Kunming University of Science and Technology
| | - Lei Wang
- Department of Medical Genetics, The First People's Hospital of Yunnan Province, The Affiliated Hospital of Kunming University of Science and Technology
| | - Jingjing Guo
- Department of Medical Genetics, The First People's Hospital of Yunnan Province, The Affiliated Hospital of Kunming University of Science and Technology
| | - Chanchan Jin
- Department of Medical Genetics, The First People's Hospital of Yunnan Province, The Affiliated Hospital of Kunming University of Science and Technology
| | - Sean Tighe
- Tissue Tech, Inc., Ocular Surface Center, and Ocular Surface Research & Education Foundation, Miami, FL
| | - Yuan Zhang
- Tissue Tech, Inc., Ocular Surface Center, and Ocular Surface Research & Education Foundation, Miami, FL
| | - Yingting Zhu
- Tissue Tech, Inc., Ocular Surface Center, and Ocular Surface Research & Education Foundation, Miami, FL
| | - Baosheng Zhu
- Department of Medical Genetics, The First People's Hospital of Yunnan Province, The Affiliated Hospital of Kunming University of Science and Technology
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37
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Constraints of carrier screening in spinal muscular atrophy: Co-existence of deletion and duplication in SMN1 gene and false negative MLPA result. GENE REPORTS 2019. [DOI: 10.1016/j.genrep.2019.100440] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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38
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Carrier frequency of spinal muscular atrophy in Thailand. Neurol Sci 2019; 40:1729-1732. [DOI: 10.1007/s10072-019-03885-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Accepted: 04/04/2019] [Indexed: 01/20/2023]
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39
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Zhang L, Bao Y, Riaz M, Tiller J, Liew D, Zhuang X, Amor DJ, Huq A, Petelin L, Nelson M, James PA, Winship I, McNeil JJ, Lacaze P. Population genomic screening of all young adults in a health-care system: a cost-effectiveness analysis. Genet Med 2019; 21:1958-1968. [PMID: 30773532 PMCID: PMC6752319 DOI: 10.1038/s41436-019-0457-6] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Accepted: 01/29/2019] [Indexed: 11/17/2022] Open
Abstract
Purpose To consider the impact and cost-effectiveness of offering preventive population genomic screening to all young adults in a single-payer health-care system. Methods We modeled screening of 2,688,192 individuals, all adults aged 18–25 years in Australia, for pathogenic variants in BRCA1/BRCA2/MLH1/MSH2 genes, and carrier screening for cystic fibrosis (CF), spinal muscular atrophy (SMA), and fragile X syndrome (FXS), at 71% testing uptake using per-test costs ranging from AUD$200 to $1200 (~USD$140 to $850). Investment costs included genetic counseling, surveillance, and interventions (reimbursed only) for at-risk individuals/couples. Cost-effectiveness was defined below AUD$50,000/DALY (disability-adjusted life year) prevented, using an incremental cost-effectiveness ratio (ICER), compared with current targeted testing. Outcomes were cancer incidence/mortality, disease cases, and treatment costs reduced. Results Population screening would reduce variant-attributable cancers by 28.8%, cancer deaths by 31.2%, and CF/SMA/FXS cases by 24.8%, compared with targeted testing. Assuming AUD$400 per test, investment required would be between 4 and 5 times higher than current expenditure. However, screening would lead to substantial savings in medical costs and DALYs prevented, at a highly cost-effective ICER of AUD$4038/DALY. At AUD$200 per test, screening would approach cost-saving for the health system (ICER = AUD$22/DALY). Conclusion Preventive genomic screening in early adulthood would be highly cost-effective in a single-payer health-care system, but ethical issues must be considered.
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Affiliation(s)
- Lei Zhang
- Department of Epidemiology and Biostatistics, School of Public Health, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, PR China.,Department of Epidemiology and Preventive Medicine, School of Public Health and Preventive Medicine, Monash University, Melbourne, VIC, Australia
| | - Yining Bao
- Department of Epidemiology and Preventive Medicine, School of Public Health and Preventive Medicine, Monash University, Melbourne, VIC, Australia.,School of Public Health, Nantong University, Nantong, Jiangsu, China
| | - Moeen Riaz
- Department of Epidemiology and Preventive Medicine, School of Public Health and Preventive Medicine, Monash University, Melbourne, VIC, Australia
| | - Jane Tiller
- Department of Epidemiology and Preventive Medicine, School of Public Health and Preventive Medicine, Monash University, Melbourne, VIC, Australia
| | - Danny Liew
- Department of Epidemiology and Preventive Medicine, School of Public Health and Preventive Medicine, Monash University, Melbourne, VIC, Australia
| | - Xun Zhuang
- School of Public Health, Nantong University, Nantong, Jiangsu, China
| | - David J Amor
- Victorian Clinical Genetics Services; Murdoch Children's Research Institute; Department of Paediatrics, University of Melbourne, Royal Children's Hospital, Parkville, VIC, Australia
| | - Aamira Huq
- Department of Genomic Medicine, Royal Melbourne Hospital; Department of Medicine, Royal Melbourne Hospital, University of Melbourne, Melbourne, VIC, Australia
| | - Lara Petelin
- Familial Cancer Centre, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia
| | - Mark Nelson
- Discipline of General Practice, University of Tasmania, Hobart, TAS, Australia
| | - Paul A James
- Department of Genomic Medicine, Royal Melbourne Hospital; Department of Medicine, Royal Melbourne Hospital, University of Melbourne, Melbourne, VIC, Australia
| | - Ingrid Winship
- Department of Genomic Medicine, Royal Melbourne Hospital; Department of Medicine, Royal Melbourne Hospital, University of Melbourne, Melbourne, VIC, Australia
| | - John J McNeil
- Department of Epidemiology and Preventive Medicine, School of Public Health and Preventive Medicine, Monash University, Melbourne, VIC, Australia
| | - Paul Lacaze
- Department of Epidemiology and Preventive Medicine, School of Public Health and Preventive Medicine, Monash University, Melbourne, VIC, Australia.
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Boemer F, Caberg JH, Dideberg V, Dardenne D, Bours V, Hiligsmann M, Dangouloff T, Servais L. Newborn screening for SMA in Southern Belgium. Neuromuscul Disord 2019; 29:343-349. [PMID: 31030938 DOI: 10.1016/j.nmd.2019.02.003] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Revised: 02/07/2019] [Accepted: 02/11/2019] [Indexed: 11/29/2022]
Abstract
Approval was recently granted for a new treatment for spinal muscular atrophy (SMA). Given that the treatment is effective when administered early and the societal burden of SMA-related disability, the implementation of a newborn screening program is warranted. We describe the stepwise process that led us to launch a newborn screening program for SMA in Southern Belgium. Different political, ethical, and clinical partners were informed about this project and were involved in its governance, as were genetic and screening labs. We developed and validated a newborn screening method to specifically recognize homozygous deletions of exon 7 in the SMN1 gene. Subsequently, a 3-year pilot study has been recently initiated in one Belgian neonatal screening laboratory to cover 17.000 neonates per year. Coverage extension to all of Southern Belgium to screen 55.000 babies each year is underway.
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Affiliation(s)
- François Boemer
- Biochemical Genetics Lab, Department of Human Genetics, CHU of Liege, University of Liege, Liege 4000, Belgium.
| | - Jean-Hubert Caberg
- Molecular Genetics Lab, Department of Human Genetics, CHU of Liege, University of Liege, Liege, Belgium
| | - Vinciane Dideberg
- Molecular Genetics Lab, Department of Human Genetics, CHU of Liege, University of Liege, Liege, Belgium
| | - Domien Dardenne
- Molecular Genetics Lab, Department of Human Genetics, CHU of Liege, University of Liege, Liege, Belgium
| | - Vincent Bours
- Department of Human Genetics, CHU of Liege, University of Liege, Liege, Belgium
| | - Mickaël Hiligsmann
- Department of Health Services Research, CAPHRI Care and Public Health Research Institute, Maastricht University, Maastricht, The Netherlands
| | - Tamara Dangouloff
- I-Motion, Platform for Pediatric Clinical Trials, Arnold Trousseau Hospital, Paris, France; Neuromuscular Center, CHR Citadelle, University of Liege, Liege, Belgium
| | - Laurent Servais
- I-Motion, Platform for Pediatric Clinical Trials, Arnold Trousseau Hospital, Paris, France; Neuromuscular Center, CHR Citadelle, University of Liege, Liege, Belgium
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Tizzano EF, Zafeiriou D. Prenatal aspects in spinal muscular atrophy: From early detection to early presymptomatic intervention. Eur J Paediatr Neurol 2018; 22:944-950. [PMID: 30219357 DOI: 10.1016/j.ejpn.2018.08.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Revised: 08/23/2018] [Accepted: 08/29/2018] [Indexed: 01/22/2023]
Abstract
With the recent advances in spinal muscular atrophy therapies, the complete scenario of standard of care and following up is changing not only in the clinical field with new phenotypes emerging but also with new expectations for patients, caregivers and health providers. The actual evidence indicates that early intervention and treatment is crucial for better response and prognosis. Knowledge of the prenatal and pre-symptomatic postnatal stages of the disease are becoming essential to consider the opportunities of timely diagnosis and to decide the earliest therapeutic intervention.
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Affiliation(s)
- Eduardo F Tizzano
- Department of Clinical and Molecular Genetics and Rare Diseases Unit and Medicine Genetics Group, VHIR, Hospital Valle Hebron, Barcelona, Spain; CIBERER, Barcelona, Spain.
| | - Dimitrios Zafeiriou
- 1st Department of Pediatrics, "Hippokratio" General Hospital, Aristotle University, Thessaloniki, Greece.
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Using Systems Biology and Mathematical Modeling Approaches in the Discovery of Therapeutic Targets for Spinal Muscular Atrophy. ADVANCES IN NEUROBIOLOGY 2018. [PMID: 30334226 DOI: 10.1007/978-3-319-94593-4_10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register]
Abstract
Systems biology uses a combination of experimental and mathematical approaches to investigate the complex and dynamic interactions with a given system or biological process. Systems biology integrates genetics, signal transduction, biochemistry and cell biology with mathematical modeling. It can be used to identify novel pathways implicated in diseases as well as to understand the mechanisms by which a specific gene is regulated. This review describes the development of mathematical models for the regulation of an endogenous modifier gene, SMN2, in spinal muscular atrophy-an early-onset motor neuron disease that is a leading genetic cause of infant mortality worldwide-by cAMP signaling. These mathematical models not only can aid in understanding how SMN2 expression is regulated but they can also be used to examine the best ways to manipulate cAMP signaling to maximally increase SMN2 expression. These models will lead to the development of therapeutic strategies for treating SMA. This systems biology approach can also be applied to other neurological diseases, particularly those in which a disease-causing gene or a modifier gene has been identified.
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Ross LF, Clarke AJ. A Historical and Current Review of Newborn Screening for Neuromuscular Disorders From Around the World: Lessons for the United States. Pediatr Neurol 2017; 77:12-22. [PMID: 29079012 DOI: 10.1016/j.pediatrneurol.2017.08.012] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Revised: 07/31/2017] [Accepted: 08/20/2017] [Indexed: 01/16/2023]
Abstract
BACKGROUND We aimed to review the history of newborn screening for three neuromuscular disorders (Duchenne muscular dystrophy, Pompe disease, and spinal muscular atrophy [SMA]) to determine best practices. METHODS The history of newborn screening for Duchenne muscular dystrophy began in 1975 with the measurement of creatinine kinase on newborn male blood spots from two Midwestern hospitals in the United States. Over the next 40 years, ten programs were implemented around the globe although none currently remain. The first experimental pilot program for Pompe disease began in 2005 in Taiwan. In 2013, Missouri was the first US state to implement Pompe newborn screening before its inclusion in the Recommended Uniform Screening Panel (RUSP) in 2015 by the Advisory Committee on Heritable Disorders in Newborns and Children (United States). In 2008, SMA was reviewed and rejected for inclusion in the RUSP because no treatment existed. With the approval of nusinersen in late 2016, spinal muscular atrophy is being reconsidered for the RUSP. RESULTS A condition should meet public health screening criteria to be included in the RUSP. Duchenne muscular dystrophy, Pompe, and SMA challenge traditional screening criteria: Duchenne muscular dystrophy does not present in infancy and lacks effective treatment; Pompe and SMA may not present until adulthood; and safety and efficacy of long-term intrathecal treatment for SMA is unknown. Potential reproductive benefit and improved research recruitment do not justify a public health screening program. CONCLUSIONS This review provides lessons that could benefit US public health departments as they consider expanding screening to include neuromuscular disorders like Duchenne muscular dystrophy, Pompe, and SMA.
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Affiliation(s)
- Lainie Friedman Ross
- Clinical Ethics, Departments of Pediatrics, Medicine, Surgery and the College, MacLean Center for Clinical Medical Ethics, University of Chicago, Chicago Illinois.
| | - Angus John Clarke
- Clinical Genetics, Institute of Cancer & Genetics, School of Medicine, Cardiff University, Cardiff, UK
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Chien YH, Chiang SC, Weng WC, Lee NC, Lin CJ, Hsieh WS, Lee WT, Jong YJ, Ko TM, Hwu WL. Presymptomatic Diagnosis of Spinal Muscular Atrophy Through Newborn Screening. J Pediatr 2017; 190:124-129.e1. [PMID: 28711173 DOI: 10.1016/j.jpeds.2017.06.042] [Citation(s) in RCA: 97] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Revised: 05/15/2017] [Accepted: 06/16/2017] [Indexed: 11/15/2022]
Abstract
OBJECTIVE To demonstrate the feasibility of presymptomatic diagnosis of spinal muscular atrophy (SMA) through newborn screening (NBS). STUDY DESIGN We performed a screening trial to assess all newborns who underwent routine newborn metabolic screening at the National Taiwan University Hospital newborn screening center between November 2014 and September 2016. A real-time polymerase chain reaction (RT-PCR) genotyping assay for the SMN1/SMN2 intron 7 c.888+100A/G polymorphism was performed to detect homozygous SMN1 deletion using dried blood spot (DBS) samples. Then the exon 7 c.840C>T mutation and SMN2 copy number were determined by both droplet digital PCR (ddPCR) using the original screening DBS and multiplex ligation-dependent probe amplification (MLPA) using a whole blood sample. RESULTS Of the 120 267 newborns, 15 tested positive according to the RT-PCR assay. The DBS ddPCR assay excluded 8 false-positives, and the other 7 patients were confirmed by the MLPA assay. Inclusion of the second-tier DBS ddPCR screening assay resulted in a positive prediction value of 100%. The incidence of SMA was 1 in 17 181 (95% CI, 1 in 8323 to 1 in 35 468). Two of the 3 patients with 2 copies of SMN2 and all 4 patients with 3 or 4 copies of SMN2 were asymptomatic at the time of diagnosis. Five of the 8 false-positives were caused by intragenic recombination between SMN1 and SMN2. CONCLUSION Newborn screening can detect patients affected by SMA before symptom onset and enable early therapeutic intervention. A combination of a RT-PCR and a second-tier ddPCR can accurately diagnose SMA from DBS samples with no false-positives. TRIAL REGISTRATION ClinicalTrials.gov NCT02123186.
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Affiliation(s)
- Yin-Hsiu Chien
- Department of Medical Genetics, National Taiwan University Hospital, Taipei, Taiwan; Department of Pediatrics, National Taiwan University Hospital, Taipei, Taiwan
| | - Shu-Chuan Chiang
- Department of Medical Genetics, National Taiwan University Hospital, Taipei, Taiwan
| | - Wen-Chin Weng
- Department of Pediatrics, National Taiwan University Hospital, Taipei, Taiwan
| | - Ni-Chung Lee
- Department of Medical Genetics, National Taiwan University Hospital, Taipei, Taiwan; Department of Pediatrics, National Taiwan University Hospital, Taipei, Taiwan
| | - Ching-Jie Lin
- Department of Medical Genetics, National Taiwan University Hospital, Taipei, Taiwan
| | - Wu-Shiun Hsieh
- Department of Pediatrics, National Taiwan University Hospital, Taipei, Taiwan
| | - Wang-Tso Lee
- Department of Pediatrics, National Taiwan University Hospital, Taipei, Taiwan
| | - Yuh-Jyh Jong
- Department of Biological Science and Technology, College of Biological Science and Technology, National Chiao Tung University, Hsinchu, Taiwan; Graduate Institute of Clinical Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Department of Pediatrics and Laboratory Medicine, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
| | - Tsang-Ming Ko
- Genephile Bioscience Laboratory, Ko's Obstetrics and Gynecology, Taipei, Taiwan
| | - Wuh-Liang Hwu
- Department of Medical Genetics, National Taiwan University Hospital, Taipei, Taiwan; Department of Pediatrics, National Taiwan University Hospital, Taipei, Taiwan.
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Pilot study of population-based newborn screening for spinal muscular atrophy in New York state. Genet Med 2017; 20:608-613. [PMID: 29758563 DOI: 10.1038/gim.2017.152] [Citation(s) in RCA: 76] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Accepted: 07/26/2017] [Indexed: 12/28/2022] Open
Abstract
PurposeTo determine feasibility and utility of newborn screening for spinal muscular atrophy (SMA) in New York State.MethodsWe validated a multiplex TaqMan real-time quantitative polymerase chain reaction assay using dried blood spots for SMA. From January 2016 to January 2017, we offered, consented, and screened 3,826 newborns at three hospitals in New York City and tested newborns for the deletion in exon 7 of SMN1.ResultsNinety-three percent of parents opted in for SMA screening. Overall the SMA carrier frequency was 1.5%. We identified one newborn with a homozygous SMN1 deletion and two copies of SMN2, which strongly suggests the severe type 1 SMA phenotype. The infant was enrolled in the NURTURE clinical trial and was first treated with Spinraza at age 15 days. She is now age 12 months, meeting all developmental milestones, and free of any respiratory issues.ConclusionOur pilot study demonstrates the feasibility of population-based screening, the acceptance by families, and the benefit of newborn screening for SMA. We suggest that SMA be considered for addition to the national recommended uniform screening panel.
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Verhaart IEC, Robertson A, Wilson IJ, Aartsma-Rus A, Cameron S, Jones CC, Cook SF, Lochmüller H. Prevalence, incidence and carrier frequency of 5q-linked spinal muscular atrophy - a literature review. Orphanet J Rare Dis 2017; 12:124. [PMID: 28676062 PMCID: PMC5496354 DOI: 10.1186/s13023-017-0671-8] [Citation(s) in RCA: 345] [Impact Index Per Article: 49.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Accepted: 06/13/2017] [Indexed: 12/14/2022] Open
Abstract
Spinal muscular atrophy linked to chromosome 5q (SMA) is a recessive, progressive, neuromuscular disorder caused by bi-allelic mutations in the SMN1 gene, resulting in motor neuron degeneration and variable presentation in relation to onset and severity. A prevalence of approximately 1-2 per 100,000 persons and incidence around 1 in 10,000 live births have been estimated with SMA type I accounting for around 60% of all cases. Since SMA is a relatively rare condition, studies of its prevalence and incidence are challenging. Most published studies are outdated and therefore rely on clinical rather than genetic diagnosis. Furthermore they are performed in small cohorts in small geographical regions and only study European populations. In addition, the heterogeneity of the condition can lead to delays and difficulties in diagnosing the condition, especially outside of specialist clinics, and contributes to the challenges in understanding the epidemiology of the disease. The frequency of unaffected, heterozygous carriers of the SMN1 mutations appears to be higher among Caucasian and Asian populations compared to the Black (Sub-Saharan African ancestry) population. However, carrier frequencies cannot directly be translated into incidence and prevalence, as very severe (death in utero) and very mild (symptom free in adults) phenotypes carrying bi-allelic SMN1 mutations exist, and their frequency is unknown. More robust epidemiological data on SMA covering larger populations based on accurate genetic diagnosis or newborn screening would be helpful to support planning of clinical studies, provision of care and therapies and evaluation of outcomes.
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Affiliation(s)
- Ingrid E. C. Verhaart
- John Walton Muscular Dystrophy Research Centre, Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, UK
| | - Agata Robertson
- John Walton Muscular Dystrophy Research Centre, Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, UK
| | - Ian J. Wilson
- Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, UK
| | - Annemieke Aartsma-Rus
- John Walton Muscular Dystrophy Research Centre, Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, UK
| | - Shona Cameron
- John Walton Muscular Dystrophy Research Centre, Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, UK
| | | | | | - Hanns Lochmüller
- John Walton Muscular Dystrophy Research Centre, Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, UK
- John Walton Muscular Dystrophy Research Centre, MRC Centre for Neuromuscular Diseases, Institute of Genetic Medicine, Newcastle University, Central Parkway, Newcastle upon Tyne, NE1 3BZ UK
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Boardman FK, Young PJ, Griffiths FE. Population screening for spinal muscular atrophy: A mixed methods study of the views of affected families. Am J Med Genet A 2016; 173:421-434. [PMID: 27792846 DOI: 10.1002/ajmg.a.38031] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Accepted: 10/07/2016] [Indexed: 11/08/2022]
Abstract
Autosomal recessive conditions are a significant health burden with few treatments. Population carrier screening has been suggested as a means to tackle them. Little is known about the views of affected families despite the potential for direct impacts on them. Data are presented on attitudes among families affected by Spinal Muscular Atrophy (SMA) toward two population screening programs, pre-conception, and prenatal. Data were gathered through qualitative interviews (n = 36) and a survey (n = 337). Eighty-two survey participants had SMA and 255 were family members. The majority were in favor of screening (75%). Reasons for supporting pre-conception screening support were a belief that it would reduce SMA-related terminations and raise awareness of SMA in the population. For prenatal screening, reasons for support included a belief in the importance of informed decision-making and the need to reduce suffering. Key reasons for non-support of pre-conception screening included concerns about carrier stigmatization and social engineering. For prenatal screening, concerns focused on the collateral loss of high quality of life lives affected by SMA. This study highlights that those affected by SMA are predominantly in favor of screening, although pre-conception screening is most favored. While family members and adults with SMA had largely consistent views, perceptions varied according to the severity (type) of SMA, with those affected by SMA type II the least likely to support screening. These findings suggest that screening for SMA is a complex issue for affected families, underscoring the need to consider and include their views when planning and implementing screening programs. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Felicity K Boardman
- Division of Health Sciences, Warwick Medical School, University of Warwick, Coventry, United Kingdom
| | - Philip J Young
- School of Life Sciences, University of Warwick, Coventry, United Kingdom
| | - Frances E Griffiths
- Division of Health Sciences, Warwick Medical School, University of Warwick, Coventry, United Kingdom
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Wei X, Tan H, Yang P, Zhang R, Tan B, Zhang Y, Mei L, Liang D, Wu L. Notable Carrier Risks for Individuals Having Two Copies of SMN1 in Spinal Muscular Atrophy Families with 2-copy Alleles: Estimation Based on Chinese Meta-analysis Data. J Genet Couns 2016; 26:72-78. [DOI: 10.1007/s10897-016-9980-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Accepted: 05/24/2016] [Indexed: 01/29/2023]
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Butchbach MER. Copy Number Variations in the Survival Motor Neuron Genes: Implications for Spinal Muscular Atrophy and Other Neurodegenerative Diseases. Front Mol Biosci 2016; 3:7. [PMID: 27014701 PMCID: PMC4785180 DOI: 10.3389/fmolb.2016.00007] [Citation(s) in RCA: 109] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Accepted: 02/25/2016] [Indexed: 12/11/2022] Open
Abstract
Proximal spinal muscular atrophy (SMA), a leading genetic cause of infant death worldwide, is an early-onset, autosomal recessive neurodegenerative disease characterized by the loss of spinal α-motor neurons. This loss of α-motor neurons is associated with muscle weakness and atrophy. SMA can be classified into five clinical grades based on age of onset and severity of the disease. Regardless of clinical grade, proximal SMA results from the loss or mutation of SMN1 (survival motor neuron 1) on chromosome 5q13. In humans a large tandem chromosomal duplication has lead to a second copy of the SMN gene locus known as SMN2. SMN2 is distinguishable from SMN1 by a single nucleotide difference that disrupts an exonic splice enhancer in exon 7. As a result, most of SMN2 mRNAs lack exon 7 (SMNΔ7) and produce a protein that is both unstable and less than fully functional. Although only 10–20% of the SMN2 gene product is fully functional, increased genomic copies of SMN2 inversely correlates with disease severity among individuals with SMA. Because SMN2 copy number influences disease severity in SMA, there is prognostic value in accurate measurement of SMN2 copy number from patients being evaluated for SMA. This prognostic value is especially important given that SMN2 copy number is now being used as an inclusion criterion for SMA clinical trials. In addition to SMA, copy number variations (CNVs) in the SMN genes can affect the clinical severity of other neurological disorders including amyotrophic lateral sclerosis (ALS) and progressive muscular atrophy (PMA). This review will discuss how SMN1 and SMN2 CNVs are detected and why accurate measurement of SMN1 and SMN2 copy numbers is relevant for SMA and other neurodegenerative diseases.
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Affiliation(s)
- Matthew E R Butchbach
- Center for Applied Clinical Genomics, Nemours Biomedical Research, Nemours Alfred I. duPont Hospital for ChildrenWilmington, DE, USA; Center for Pediatric Research, Nemours Biomedical Research, Nemours Alfred I. duPont Hospital for ChildrenWilmington, DE, USA; Department of Biological Sciences, University of DelawareNewark, DE, USA; Department of Pediatrics, Thomas Jefferson UniversityPhiladelphia, PA, USA
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