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Wu R, Li X, Meng Z, Li P, He Z, Liang L. Phenotypic and genetic analysis of children with unexplained neurodevelopmental delay and neurodevelopmental comorbidities in a Chinese cohort using trio-based whole-exome sequencing. Orphanet J Rare Dis 2024; 19:205. [PMID: 38764027 PMCID: PMC11103872 DOI: 10.1186/s13023-024-03214-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: 02/20/2023] [Accepted: 05/10/2024] [Indexed: 05/21/2024] Open
Abstract
BACKGROUND Trio-based whole-exome sequencing (trio-WES) enables identification of pathogenic variants, including copy-number variants (CNVs), in children with unexplained neurodevelopmental delay (NDD) and neurodevelopmental comorbidities (NDCs), including autism spectrum disorder (ASD), epilepsy, and attention deficit hyperactivity disorder. Further phenotypic and genetic analysis on trio-WES-tested NDD-NDCs cases may help to identify key phenotypic factors related to higher diagnostic yield of using trio-WES and novel risk genes associated with NDCs in clinical settings. METHODS In this study, we retrospectively performed phenotypic analysis on 163 trio-WES-tested NDD-NDCs children to determine the phenotypic differences between genetically diagnosed and non-genetically diagnosed groups. Additionally, we conducted genetic analysis of ASD genes with the help of Simons Foundation for Autism Research Institute (SFARI) Gene database to identify novel possible ASD-risk genes underlying genetic NDD conditions. RESULTS Among these 163 patients, pathogenic variants were identified in 82 cases (82/163, 50.3%), including 20 cases with CNVs. By comparing phenotypic variables between genetically diagnosed group (82 cases) and non-genetically diagnosed group (81 cases) with multivariate binary logistic regression analysis, we revealed that NDD-NDCs cases presenting with severe-profound NDD [53/82 vs 17/81, adjusted-OR (95%CI): 4.865 (2.213 - 10.694), adjusted-P < 0.001] or having multiple NDCs [26/82 vs 8/81, adjusted-OR (95%CI): 3.731 (1.399 - 9.950), adjusted-P = 0.009] or accompanying ASD [64/82 vs 35/81, adjusted-OR (95%CI): 3.256 (1.479 - 7.168), adjusted-P = 0.003] and head circumference abnormality [33/82 vs 11/81, adjusted-OR (95%CI): 2.788 (1.148 - 6.774), adjusted-P = 0.024] were more likely to have a genetic diagnosis using trio-WES. Moreover, 37 genes with monogenetic variants were identified in 48 patients genetically diagnosed with NDD-ASD, and 15 dosage-sensitive genes were identified in 16 individuals with NDD-ASD carrying CNVs. Most of those genes had been proven to be ASD-related genes. However, some of them (9 genes) were not proven sufficiently to correlate with ASD. By literature review and constructing protein-protein interaction networks among these 9 candidate ASD-risk genes and 102 established ASD genes obtained from the SFARI Gene database, we identified CUL4B, KCNH1, and PLA2G6 as novel possible ASD-risk genes underlying genetic NDD conditions. CONCLUSIONS Trio-WES testing is recommended for patients with unexplained NDD-NDCs that have severe-profound NDD or multiple NDCs, particularly those with accompanying ASD and head circumference abnormality, as these independent factors may increase the likelihood of genetic diagnosis using trio-WES. Moreover, NDD patients with pathogenic variants in CUL4B, KCNH1 and PLA2G6 should be aware of potential risks of developing ASD during their disease courses.
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Affiliation(s)
- Ruohao Wu
- Department of Children's Neuro-endocrinology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, 510120, Guangdong, China
- Children's Medical Center, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou Guangdong, 510120, China
| | - Xiaojuan Li
- Department of Research and Molecular Diagnostics, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, 510120, Guangdong, China
| | - Zhe Meng
- Department of Children's Neuro-endocrinology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, 510120, Guangdong, China
- Children's Medical Center, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou Guangdong, 510120, China
| | - Pinggan Li
- Department of Children's Neuro-endocrinology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, 510120, Guangdong, China
- Children's Medical Center, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou Guangdong, 510120, China
| | - Zhanwen He
- Department of Children's Neuro-endocrinology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, 510120, Guangdong, China.
- Children's Medical Center, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou Guangdong, 510120, China.
| | - Liyang Liang
- Department of Children's Neuro-endocrinology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, 510120, Guangdong, China.
- Children's Medical Center, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou Guangdong, 510120, China.
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Chaves TF, Ocampos M, Barbato IT, de Camargo Pinto LL, de Luca GR, Barbato Filho JH, Bernardi P, Costa Netto Muniz Y, Francesca Maris A. A cohort study of neurodevelopmental disorders and/or congenital anomalies using high resolution chromosomal microarrays in southern Brazil highlighting the significance of ASD. Sci Rep 2024; 14:3762. [PMID: 38355898 PMCID: PMC10867078 DOI: 10.1038/s41598-024-54385-2] [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: 11/10/2023] [Accepted: 02/12/2024] [Indexed: 02/16/2024] Open
Abstract
Chromosomal microarray (CMA) is the reference in evaluation of copy number variations (CNVs) in individuals with neurodevelopmental disorders (NDDs), such as intellectual disability (ID) and/or autism spectrum disorder (ASD), which affect around 3-4% of the world's population. Modern platforms for CMA, also include probes for single nucleotide polymorphisms (SNPs) that detect homozygous regions in the genome, such as long contiguous stretches of homozygosity (LCSH). These regions result from complete or segmental chromosomal homozygosis and may be indicative of uniparental disomy (UPD), inbreeding, population characteristics, as well as replicative DNA repair events. In this retrospective study, we analyzed CMA reading files requested by geneticists and neurologists for diagnostic purposes along with available clinical data. Our objectives were interpreting CNVs and assess the frequencies and implications of LCSH detected by Affymetrix CytoScan HD (41%) or 750K (59%) platforms in 1012 patients from the south of Brazil. The patients were mainly children with NDDs and/or congenital anomalies (CAs). A total of 206 CNVs, comprising 132 deletions and 74 duplications, interpreted as pathogenic, were found in 17% of the patients in the cohort and across all chromosomes. Additionally, 12% presented rare variants of uncertain clinical significance, including LPCNVs, as the only clinically relevant CNV. Within the realm of NDDs, ASD carries a particular importance, owing to its escalating prevalence and its growing repercussions for individuals, families, and communities. ASD was one clinical phenotype, if not the main reason for referral to testing, for about one-third of the cohort, and these patients were further analyzed as a sub-cohort. Considering only the patients with ASD, the diagnostic rate was 10%, within the range reported in the literature (8-21%). It was higher (16%) when associated with dysmorphic features and lower (7%) for "isolated" ASD (without ID and without dysmorphic features). In 953 CMAs of the whole cohort, LCSH (≥ 3 Mbp) were analyzed not only for their potential pathogenic significance but were also explored to identify common LCSH in the South Brazilians population. CMA revealed at least one LCSH in 91% of the patients. For about 11.5% of patients, the LCSH suggested consanguinity from the first to the fifth degree, with a greater probability of clinical impact, and in 2.8%, they revealed a putative UPD. LCSH found at a frequency of 5% or more were considered common LCSH in the general population, allowing us to delineate 10 regions as potentially representing ancestral haplotypes of neglectable clinical significance. The main referrals for CMA were developmental delay (56%), ID (33%), ASD (33%) and syndromic features (56%). Some phenotypes in this population may be predictive of a higher probability of indicating a carrier of a pathogenic CNV. Here, we present the largest report of CMA data in a cohort with NDDs and/or CAs from the South of Brazil. We characterize the rare CNVs found along with the main phenotypes presented by each patient and show the importance and usefulness of LCSH interpretation in CMA results that incorporate SNPs, as well as we illustrate the value of CMA to investigate CNV in ASD.
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Affiliation(s)
- Tiago Fernando Chaves
- Laboratório de Polimorfismos Genéticos (LAPOGE), Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil.
- Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil.
| | - Maristela Ocampos
- Laboratory Neurogene (former), Florianopolis, SC, Brazil
- Mercolab Diagnóstica (actual), Florianopolis, SC, Brazil
| | | | | | | | | | - Priscila Bernardi
- University Hospital Professor Polydoro Ernani de São Thiago, Florianópolis, SC, Brazil
| | - Yara Costa Netto Muniz
- Laboratório de Polimorfismos Genéticos (LAPOGE), Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil
| | - Angelica Francesca Maris
- Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil.
- Children's Hospital Joana de Gusmão, Florianópolis, SC, Brazil.
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Wu D, Wu Y, Lan Y, Lan S, Zhong Z, Li D, Zheng Z, Wang H, Ma L. Chromosomal Aberrations in Pediatric Patients With Moderate/Severe Developmental Delay/Intellectual Disability With Abundant Phenotypic Heterogeneities: A Single-Center Study. Pediatr Neurol 2023; 147:72-81. [PMID: 37566956 DOI: 10.1016/j.pediatrneurol.2023.06.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Revised: 05/26/2023] [Accepted: 06/06/2023] [Indexed: 08/13/2023]
Abstract
BACKGROUND This study aimed to examine the clinical usefulness of chromosome microarray (CMA) for selective implementation in patients with unexplained moderate or severe developmental delay/intellectual disability (DD/ID) and/or combined with different dysphonic features in the Han Chinese population. METHODS We retrospectively analyzed data on 122 pediatric patients with unexplained isolated moderate/severe DD/ID with or without autism spectrum disorders, epilepsy, dystonia, and congenital abnormalities from a single-center neurorehabilitation clinic in southern China. RESULTS A total of 46 probands (37.7%) had abnormal CMA results among the 122 study patients. With the exclusion of aneuploidies, uniparental disomies, and multiple homozygotes, 37 patients harbored 39 pathogenic copy number variations (pCNVs) (median [interquartile range] size: 3.57 [1.6 to 7.1] Mb; 33 deletions and 6 duplications), enriched in chromosomes 5, 7, 15, 17, and 22, with a markedly high prevalence of Angelman/Prader-Willi syndrome (24.3% [nine of 37]). Three rare deletions in the regions 5q33.2q34, 17p13.2, and 13q33.2 were reported, with specific delineation of clinical phenotypes. The frequencies of pCNVs were 18%, 33.3%, 38.89%, 41.67%, and 100% for patients with 1, 2, 3, 4, and 5 study phenotypes, respectively; patients with more concomitant abnormalities in the heart, brain, craniofacial region, and/or other organs had a higher CMA diagnostic yield and pCNV prevalence (P < 0.05). CONCLUSIONS Clinical application of CMA as a first-tier test among patients with moderate/severe DD/ID combined with congenital structural anomalies improved diagnostic yields and the quality of clinical management in this series of patients.
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Affiliation(s)
- Dan Wu
- Department of Pediatrics, Second Affiliated Hospital of Shantou University Medical College, Shantou, Guangdong, China; Centre for Precision Health, School of Medical and Health Sciences, Edith Cowan University, Perth, WA, Australia
| | - Yi Wu
- Department of Pediatrics, Second Affiliated Hospital of Shantou University Medical College, Shantou, Guangdong, China
| | - Yulong Lan
- Centre for Precision Health, School of Medical and Health Sciences, Edith Cowan University, Perth, WA, Australia; Department of Cardiology, Second Affiliated Hospital of Shantou University Medical College, Shantou, Guangdong, China
| | - Shaocong Lan
- Guangdong Medical College, Zhanjiang, Guangdong, China
| | - Zhiwei Zhong
- Department of Neurosurgery, The First Affiliated Hospital of Shantou University Medical College, Shantou, Guangdong, China
| | - Duo Li
- Department of Pediatrics, Second Affiliated Hospital of Shantou University Medical College, Shantou, Guangdong, China
| | - Zexin Zheng
- Department of Pediatrics, Second Affiliated Hospital of Shantou University Medical College, Shantou, Guangdong, China
| | - Hongwu Wang
- Department of Pediatrics, Second Affiliated Hospital of Shantou University Medical College, Shantou, Guangdong, China.
| | - Lian Ma
- Department of Pediatrics, Second Affiliated Hospital of Shantou University Medical College, Shantou, Guangdong, China; Department of Hematology and Oncology, Shenzhen Children's Hospital of China Medical University, Shenzhen, Guangdong, China; Shenzhen Public Service Platform of Molecular Medicine in Pediatric Hematology and Oncology, Shenzhen, Guangdong, China; Department of Pediatrics, The Third Affiliated Hospital of Guangzhou Medical University (The Women and Children's Hospital of Guangzhou Medical University), Guangzhou, Guangdong, China.
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Genome-Wide Sequencing Modalities for Children with Unexplained Global Developmental Delay and Intellectual Disabilities—A Narrative Review. CHILDREN 2023; 10:children10030501. [PMID: 36980059 PMCID: PMC10047410 DOI: 10.3390/children10030501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2023] [Revised: 02/25/2023] [Accepted: 03/01/2023] [Indexed: 03/06/2023]
Abstract
Unexplained global developmental delay (GDD) and intellectual disabilities (ID) together affect nearly 2% of the pediatric population. Establishing an etiologic diagnosis is crucial for disease management, prognostic evaluation, and provision of physical and psychological support for both the patient and the family. Advancements in genome sequencing have allowed rapid accumulation of gene–disorder associations and have accelerated the search for an etiologic diagnosis for unexplained GDD/ID. We reviewed recent studies that utilized genome-wide analysis technologies, and we discussed their diagnostic yield, strengths, and limitations. Overall, exome sequencing (ES) and genome sequencing (GS) outperformed chromosomal microarrays and targeted panel sequencing. GS provides coverage for both ES and chromosomal microarray regions, providing the maximal diagnostic potential, and the cost of ES and reanalysis of ES-negative results is currently still lower than that of GS alone. Therefore, singleton or trio ES is the more cost-effective option for the initial investigation of individuals with GDD/ID in clinical practice compared to a staged approach or GS alone. Based on these updated evidence, we proposed an evaluation algorithm with ES as the first-tier evaluation for unexplained GDD/ID.
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The exploration of genetic aetiology and diagnostic strategy for 321 Chinese individuals with intellectual disability. Clin Chim Acta 2023; 538:94-103. [PMID: 36368352 DOI: 10.1016/j.cca.2022.10.023] [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: 08/31/2022] [Revised: 10/08/2022] [Accepted: 10/28/2022] [Indexed: 11/09/2022]
Abstract
BACKGROUND Intellectual disability is a heterogeneous neurodevelopmental disorder with complex genetic architectures. Different sequential methodologies are usually applied to identify the genetic aetiologies of ID patients. METHODS We collected 321 consecutive ID patients. All patients underwent karyotyping, while 293 and 164 cases further received copy number variation sequencing (CNV-seq) and whole-exome sequencing (WES). The updated WES technology can detect CNVs simultaneously. The diagnostic data from 137 patients who received WES and CNV-seq were used to define the approach that could be recommended as the first-tier test. RESULTS WES obtains the highest diagnostic yield of 50% (82/164), compared with karyotyping (7.79%, 25/321) and CNV-seq (19.80%, 58/293). Among the variants detected by WES, 66.67% (44/66) de novo and 57.58% (38/66) novel pathogenic/likely pathogenic (P/LP) variants were identified in patients with ID. Besides, 24 out of 25P/LP CNVs discovered by CNV-seq can also be accurately identified using WES in 137 patients who received WES and CNV-seq. Thus, genetic abnormalities found through karyotyping, CNV-seq, and WES can be completely detected by combined karyotyping and WES. CONCLUSIONS This study illustrates the genetic aberrations of a Chinese ID cohort and expands the mutation spectrum of ID-related genes. Compared with the conventional diagnostic strategy, a combination of karyotype analysis and WES could be recommended as the first-tier diagnostic strategy for ID patients.
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Zhang L, Liu X, Zhao Y, Wang Q, Zhang Y, Gao H, Zhang B, Cui W, Zhao Y. Genetic subtypes and phenotypic characteristics of 110 patients with Prader-Willi syndrome. Ital J Pediatr 2022; 48:121. [PMID: 35870983 PMCID: PMC9308266 DOI: 10.1186/s13052-022-01319-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Accepted: 07/07/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Prader-Willi syndrome (PWS) is a complex disorder caused by impaired paternally expressed genes on chromosome 15q11-q13. Variable findings have been reported about the phenotypic differences among PWS genetic subtypes. METHODS A total of 110 PWS patients were diagnosed from 8,572 pediatric patients included from July 2013 to December 2021 by MLPA and MS-MLPA assays. Atypical deletions were defined by genomic CNV-sequencing. Maternal uniparental disomy (UPD) was subgrouped by microsatellite genotyping. Clinical data were collected for phenotype-genotype associations. Twenty-one patients received growth hormone (GH) treatment, and the anthropometric and laboratory parameters were evaluated and compared. RESULTS Genetically, the 110 patients with PWS included 29 type I deletion, 56 type II deletion, 6 atypical deletion, 11 heterodisomy UPD, and 8 isodisomy UPD. The UPD group had significantly higher maternal age (31.4 ± 3.4 vs 27.8 ± 3.8 years), more anxiety (64.29% vs 26.09%) and autistic traits (57.14% vs 26.09%), and less hypopigmentation (42.11% vs 68.24%) and skin picking (42.86% vs 71.01%) than the deletion group. The type I deletion group was diagnosed at earlier age (3.7 ± 3.3 vs 6.2 ± 3.2 years) and more common in speech delay (95.45% vs 63.83%) than the type II. The isodisomy UPD group showed a higher tendency of anxiety (83.33% vs 50%) than the heterodisomy. GH treatment for 1 year significantly improved the SDS of height (- 0.43 ± 0.68 vs - 1.32 ± 1.19) and IGF-I (- 0.45 ± 0.48 vs - 1.97 ± 1.12). No significant changes were found in thyroid function or glucose/lipid metabolism. CONCLUSION We explored the physical, psychological and behavioral phenotype-genotype associations as well as the GH treatment effect on PWS from a large cohort of Chinese pediatric patients. Our data might promote pediatricians' recognition and early diagnosis of PWS.
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Affiliation(s)
- Lu Zhang
- Department of Clinical Genetics, Shengjing Hospital of China Medical University, No 36 Sanhao Street, Heping Ward, Shenyang, 110004, China
| | - Xiaoliang Liu
- Department of Clinical Genetics, Shengjing Hospital of China Medical University, No 36 Sanhao Street, Heping Ward, Shenyang, 110004, China
| | - Yunjing Zhao
- Department of Developmental Pediatrics, Shengjing Hospital of China Medical University, Shenyang, China
| | - Qingyi Wang
- Center for Computational and Integrative Biology, Massachusetts General Hospital, Boston, MA, USA
| | - Yuanyuan Zhang
- Department of Clinical Genetics, Shengjing Hospital of China Medical University, No 36 Sanhao Street, Heping Ward, Shenyang, 110004, China
| | - Haiming Gao
- Department of Clinical Genetics, Shengjing Hospital of China Medical University, No 36 Sanhao Street, Heping Ward, Shenyang, 110004, China
| | - Bijun Zhang
- Department of Clinical Genetics, Shengjing Hospital of China Medical University, No 36 Sanhao Street, Heping Ward, Shenyang, 110004, China
| | - Wanting Cui
- Department of Clinical Genetics, Shengjing Hospital of China Medical University, No 36 Sanhao Street, Heping Ward, Shenyang, 110004, China
| | - Yanyan Zhao
- Department of Clinical Genetics, Shengjing Hospital of China Medical University, No 36 Sanhao Street, Heping Ward, Shenyang, 110004, China.
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Cao Y, Luk HM, Zhang Y, Chau MHK, Xue S, Cheng SSW, Li AM, Chong JSC, Leung TY, Dong Z, Choy KW, Lo IFM. Investigation of Chromosomal Structural Abnormalities in Patients With Undiagnosed Neurodevelopmental Disorders. Front Genet 2022; 13:803088. [PMID: 35495136 PMCID: PMC9046776 DOI: 10.3389/fgene.2022.803088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Accepted: 02/04/2022] [Indexed: 11/13/2022] Open
Abstract
Background: Structural variations (SVs) are various types of the genomic rearrangements encompassing at least 50 nucleotides. These include unbalanced gains or losses of DNA segments (copy number changes, CNVs), balanced rearrangements (such as inversion or translocations), and complex combinations of several distinct rearrangements. SVs are known to play a significant role in contributing to human genomic disorders by disrupting the protein-coding genes or the interaction(s) with cis-regulatory elements. Recently, different types of genome sequencing-based tests have been introduced in detecting various types of SVs other than CNVs and regions with absence of heterozygosity (AOH) with clinical significance.Method: In this study, we applied the mate-pair low pass (∼4X) genome sequencing with large DNA-insert (∼5 kb) in a cohort of 100 patients with neurodevelopmental disorders who did not receive informative results from a routine CNV investigation. Read-depth-based CNV analysis and chimeric-read-pairs analysis were used for CNV and SV analyses. The region of AOH was indicated by a simultaneous decrease in the rate of heterozygous SNVs and increase in the rate of homozygous SNVs.Results: First, we reexamined the 25 previously reported CNVs among 24 cases in this cohort. The boundaries of these twenty-five CNVs including 15 duplications and 10 deletions detected were consistent with the ones indicated by the chimeric-read-pairs analysis, while the location and orientation were determined in 80% of duplications (12/15). Particularly, one duplication was involved in complex rearrangements. In addition, among all the 100 cases, 10% of them were detected with rare or complex SVs (>10 Kb), and 3% were with multiple AOH (≥5 Mb) locating in imprinting chromosomes identified. In particular, one patient with an overall value of 214.5 Mb of AOH identified on 13 autosomal chromosomes suspected parental consanguinity.Conclusion: In this study, mate-pair low-pass GS resolved a significant proportion of CNVs with inconclusive significance, and detected additional SVs and regions of AOH in patients with undiagnostic neurodevelopmental disorders. This approach complements the first-tier CNV analysis for NDDs, not only by increasing the resolution of CNV detection but also by enhancing the characterization of SVs and the discovery of potential causative regions (or genes) contributory to could be complex in composition NDDs.
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Affiliation(s)
- Ye Cao
- Department of Paediatrics, The Chinese University of Hong Kong, Hong Kong SAR, China
- Department of Obstetrics and Gynaecology, The Chinese University of Hong Kong, Hong Kong SAR, China
- Key Laboratory for Regenerative Medicine, Ministry of Education (Shenzhen Base), Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen, China
- Hong Kong Hub of Paediatric Excellence, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - Ho Ming Luk
- Clinical Genetic Service, Department of Health, Hong Kong SAR, China
| | - Yanyan Zhang
- Department of Obstetrics and Gynaecology, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - Matthew Hoi Kin Chau
- Department of Obstetrics and Gynaecology, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - Shuwen Xue
- Department of Obstetrics and Gynaecology, The Chinese University of Hong Kong, Hong Kong SAR, China
| | | | - Albert Martin Li
- Department of Paediatrics, The Chinese University of Hong Kong, Hong Kong SAR, China
- Hong Kong Hub of Paediatric Excellence, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - Josephine S. C. Chong
- Department of Paediatrics, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - Tak Yeung Leung
- Department of Obstetrics and Gynaecology, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - Zirui Dong
- Department of Obstetrics and Gynaecology, The Chinese University of Hong Kong, Hong Kong SAR, China
- Key Laboratory for Regenerative Medicine, Ministry of Education (Shenzhen Base), Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen, China
- Hong Kong Hub of Paediatric Excellence, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - Kwong Wai Choy
- Department of Obstetrics and Gynaecology, The Chinese University of Hong Kong, Hong Kong SAR, China
- Key Laboratory for Regenerative Medicine, Ministry of Education (Shenzhen Base), Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen, China
- *Correspondence: Kwong Wai Choy, ; Ivan Fai Man Lo,
| | - Ivan Fai Man Lo
- Clinical Genetic Service, Department of Health, Hong Kong SAR, China
- *Correspondence: Kwong Wai Choy, ; Ivan Fai Man Lo,
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Sun Y, Peng J, Liang D, Ye X, Xu N, Chen L, Yan D, Zhang H, Xiao B, Qiu W, Shen Y, Pang N, Liu Y, Liang C, Qin Z, Luo J, Chen F, Wang J, Zhang Z, Wei H, Du J, Yan H, Duan R, Wang J, Zhang Y, Liao S, Sun K, Wu L, Yu Y. Genome sequencing demonstrates high diagnostic yield in children with undiagnosed global developmental delay/intellectual disability: a prospective study. Hum Mutat 2022; 43:568-581. [PMID: 35143101 DOI: 10.1002/humu.24347] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Revised: 01/25/2022] [Accepted: 02/08/2022] [Indexed: 11/08/2022]
Abstract
Genome sequencing(GS) has been used in the diagnosis of global developmental delay(GDD)/intellectual disability(ID). However, the performance of GS in patients with inconclusive results from chromosomal microarray analysis(CMA) and exome sequencing(ES) is unknown. We recruited 100 pediatric GDD/ID patients from multiple sites in China from February 2018 to August 2020 for GS. Patients have received at least one genomic diagnostic test prior to enrollment. Reanalysis of their CMA/ES data was performed. The yield of GS was calculated and explanations for missed diagnoses by CMA/ES were investigated. Clinical utility was assessed by interviewing the parents by phone. The overall diagnostic yield of GS was 21%. Seven cases could have been solved with reanalysis of ES data. Thirteen families were missed by previous CMA/ES due to improper methodology. Two remained unsolved after ES reanalysis due to complex variants missed by ES, and a CNV in untranslated regions. Follow-up of the diagnosed families revealed that nine families experienced changes in clinical management, including identification of targeted treatments, cessation of unnecessary treatment, and considerations for family planning. GS demonstrated high diagnostic yield and clinical utility in this undiagnosed GDD/ID cohort, detecting a wide range of variant types of different sizes in a single workflow. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Yu Sun
- Department of Pediatric Endocrinology and Genetic Metabolism, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, 200092, Shanghai, China.,Shanghai Institute for Pediatric Research, 200092, Shanghai, China
| | - Jing Peng
- Department of Pediatrics, Xiangya Hospital, Central South University, 410008, Changsha, China.,Hunan Intellectual and Developmental Disabilities Research Center, 410008, Changsha, China
| | - Desheng Liang
- Center for Medical Genetics & Hunan Key Laboratory of Medical Genetics, School of Life Sciences, Central South University, 410078, Changsha, China
| | - Xiantao Ye
- Department of Pediatric Endocrinology and Genetic Metabolism, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, 200092, Shanghai, China.,Shanghai Institute for Pediatric Research, 200092, Shanghai, China
| | - Na Xu
- Department of Pediatric Endocrinology and Genetic Metabolism, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, 200092, Shanghai, China.,Shanghai Institute for Pediatric Research, 200092, Shanghai, China
| | - Linlin Chen
- Department of Pediatric Endocrinology and Genetic Metabolism, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, 200092, Shanghai, China.,Shanghai Institute for Pediatric Research, 200092, Shanghai, China
| | - Dan Yan
- Department of Pediatric Endocrinology and Genetic Metabolism, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, 200092, Shanghai, China.,Shanghai Institute for Pediatric Research, 200092, Shanghai, China
| | - Huiwen Zhang
- Department of Pediatric Endocrinology and Genetic Metabolism, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, 200092, Shanghai, China.,Shanghai Institute for Pediatric Research, 200092, Shanghai, China
| | - Bing Xiao
- Department of Pediatric Endocrinology and Genetic Metabolism, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, 200092, Shanghai, China.,Shanghai Institute for Pediatric Research, 200092, Shanghai, China
| | - Wenjuan Qiu
- Department of Pediatric Endocrinology and Genetic Metabolism, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, 200092, Shanghai, China.,Shanghai Institute for Pediatric Research, 200092, Shanghai, China
| | - Yiping Shen
- Genetic and Metabolic Central Laboratory, Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region, 530003, Nanning, China
| | - Nan Pang
- Department of Pediatrics, Xiangya Hospital, Central South University, 410008, Changsha, China.,Hunan Intellectual and Developmental Disabilities Research Center, 410008, Changsha, China
| | - Yingdi Liu
- Center for Medical Genetics & Hunan Key Laboratory of Medical Genetics, School of Life Sciences, Central South University, 410078, Changsha, China
| | - Chen Liang
- Medical Genetics Center, Jiangmen Maternity and Child Health Care Hospital, 529000, Jiangmen, China
| | - Zailong Qin
- Genetic and Metabolic Central Laboratory, Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region, 530003, Nanning, China
| | - Jingsi Luo
- Genetic and Metabolic Central Laboratory, Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region, 530003, Nanning, China
| | - Fei Chen
- Genetic and Metabolic Central Laboratory, Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region, 530003, Nanning, China
| | - Jingmin Wang
- Department of Pediatrics, Peking University First Hospital, 10034, Beijing, China
| | - Zhixin Zhang
- International Medical Services, China-Japan Friendship Hospital, 100029, Beijing, China
| | - Haiyan Wei
- Department of Endocrinologic and Inherited Metabolic, Childen's Hospital affiliated to Zhengzhou University, 450018, Zhengzhou, China
| | - Juan Du
- Reproductive and Genetic Hospital of CITIC-Xiangya, 410078, Changsha, China
| | - Huifang Yan
- Department of Pediatrics, Peking University First Hospital, 10034, Beijing, China
| | - Ruoyu Duan
- Department of Pediatrics, Peking University First Hospital, 10034, Beijing, China
| | - Junyu Wang
- Department of Pediatrics, Peking University First Hospital, 10034, Beijing, China
| | - Yu Zhang
- Department of Pediatrics, Peking University First Hospital, 10034, Beijing, China
| | - Shixiu Liao
- Provincial People's Hospital, Medical Genetics Institute of Henan Province, 450003, Zhengzhou, Henan Province, China
| | - Kun Sun
- Center for Clinical Genetics, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, 200092, Shanghai, China
| | - Lingqian Wu
- Center for Medical Genetics & Hunan Key Laboratory of Medical Genetics, School of Life Sciences, Central South University, 410078, Changsha, China
| | - Yongguo Yu
- Department of Pediatric Endocrinology and Genetic Metabolism, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, 200092, Shanghai, China.,Shanghai Institute for Pediatric Research, 200092, Shanghai, China
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9
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Zhang W, Li D, Pang N, Jiang L, Li B, Ye F, He F, Chen S, Liu F, Peng J, Yin J, Yin F. The second-tier status of fragile X syndrome testing for unexplained intellectual disability/global developmental delay in the era of next-generation sequencing. Front Pediatr 2022; 10:911805. [PMID: 35935362 PMCID: PMC9353215 DOI: 10.3389/fped.2022.911805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2022] [Accepted: 06/28/2022] [Indexed: 11/17/2022] Open
Abstract
OBJECTIVE Although many unexplained intellectual disability/global developmental delay (ID/GDD) individuals have benefited from the excellent detection yield of copy number variations and next-generation sequencing testing, many individuals still who suffer from ID/GDD of unexplained etiology. In this study, we investigated the applicability of fragile X syndrome (FXS) testing in unexplained ID/GDD individuals with negative or absent genetic testing. METHODS In this study, we used the triplet repeat primed polymerase chain reaction to evaluate the value and application of fragile X testing in unexplained ID/GDD individuals with negative or absent genetic testing (n = 681) from three hospitals. RESULTS Of the 681 ID/GDD individuals with negative or absent genetic testing results detected by FXS testing, 12 men and one woman were positive. This corresponded to a diagnostic yield of 1.9% for FXS testing in our cohort. All FXS individuals had either a family history of ID/GDD or suggestive clinical features. The detection yield of FXS testing in ID/GDD individuals who completed genetic testing (2.70%, 12/438) was significantly higher than in individuals without any genetic testing (0.40%, 1/243). CONCLUSIONS This is the first report of FXS testing in ID/GDD individuals who lacked previous genetic testing, which promotes standardization of the FXS diagnostic process. These results highlight the utility of FXS testing of unexplained ID/GDD individuals with negative results from standard genetic testing. In the era of next-generation sequencing, FXS testing is more suitable as a second-tier choice and provides clinicians and geneticists with auxiliary references for tracing the etiology of ID/GDD.
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Affiliation(s)
- Wen Zhang
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China.,Hunan Intellectual and Developmental Disabilities Research Center, Pediatrics, Changsha, China.,Clinical Research Center for Children Neurodevelopmental Disabilities of Hunan Province, Xiangya Hospital, Central South University, Changsha, China
| | - Dong Li
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China.,Hunan Intellectual and Developmental Disabilities Research Center, Pediatrics, Changsha, China.,Clinical Research Center for Children Neurodevelopmental Disabilities of Hunan Province, Xiangya Hospital, Central South University, Changsha, China
| | - Nan Pang
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China.,Hunan Intellectual and Developmental Disabilities Research Center, Pediatrics, Changsha, China.,Clinical Research Center for Children Neurodevelopmental Disabilities of Hunan Province, Xiangya Hospital, Central South University, Changsha, China
| | - Li Jiang
- Department of Neurology, Children's Hospital Affiliated to Chongqing Medical University, Chongqing, China
| | - Baomin Li
- Department of Pediatrics, Qilu Hospital of Shandong University, Jinan, China
| | - Fanghua Ye
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China
| | - Fang He
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China.,Hunan Intellectual and Developmental Disabilities Research Center, Pediatrics, Changsha, China.,Clinical Research Center for Children Neurodevelopmental Disabilities of Hunan Province, Xiangya Hospital, Central South University, Changsha, China
| | - Shimeng Chen
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China.,Hunan Intellectual and Developmental Disabilities Research Center, Pediatrics, Changsha, China.,Clinical Research Center for Children Neurodevelopmental Disabilities of Hunan Province, Xiangya Hospital, Central South University, Changsha, China
| | - Fangyun Liu
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China.,Hunan Intellectual and Developmental Disabilities Research Center, Pediatrics, Changsha, China.,Clinical Research Center for Children Neurodevelopmental Disabilities of Hunan Province, Xiangya Hospital, Central South University, Changsha, China
| | - Jing Peng
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China.,Hunan Intellectual and Developmental Disabilities Research Center, Pediatrics, Changsha, China.,Clinical Research Center for Children Neurodevelopmental Disabilities of Hunan Province, Xiangya Hospital, Central South University, Changsha, China
| | - Jinghua Yin
- Department of Pathophysiology, Xiangya Hospital, Central South University, Changsha, China
| | - Fei Yin
- Department of Pediatrics, Xiangya Hospital, Central South University, Changsha, China.,Hunan Intellectual and Developmental Disabilities Research Center, Pediatrics, Changsha, China.,Clinical Research Center for Children Neurodevelopmental Disabilities of Hunan Province, Xiangya Hospital, Central South University, Changsha, China
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10
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Cheng MC, Chien WH, Huang YS, Fang TH, Chen CH. Translational Study of Copy Number Variations in Schizophrenia. Int J Mol Sci 2021; 23:ijms23010457. [PMID: 35008879 PMCID: PMC8745588 DOI: 10.3390/ijms23010457] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 12/11/2021] [Accepted: 12/29/2021] [Indexed: 11/16/2022] Open
Abstract
Rare copy number variations (CNVs) are part of the genetics of schizophrenia; they are highly heterogeneous and personalized. The CNV Analysis Group of the Psychiatric Genomic Consortium (PGC) conducted a large-scale analysis and discovered that recurrent CNVs at eight genetic loci were pathogenic to schizophrenia, including 1q21.1, 2p16.3 (NRXN1), 3q29, 7q11.23, 15q13.3, distal 16p11.2, proximal 16p11.2, and 22q11.2. We adopted a two-stage strategy to translate this knowledge into clinical psychiatric practice. As a screening test, we first developed a real-time quantitative PCR (RT-qPCR) panel that simultaneously detected these pathogenic CNVs. Then, we tested the utility of this screening panel by investigating a sample of 557 patients with schizophrenia. Chromosomal microarray analysis (CMA) was used to confirm positive cases from the screening test. We detected and confirmed thirteen patients who carried CNVs at these hot loci, including two patients at 1q21.1, one patient at 7q11.2, three patients at 15q13.3, two patients at 16p11.2, and five patients at 22q11.2. The detection rate in this sample was 2.3%, and the concordance rate between the RT-qPCR test panel and CMA was 100%. Our results suggest that a two-stage approach is cost-effective and reliable in achieving etiological diagnosis for some patients with schizophrenia and improving the understanding of schizophrenia genetics.
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Affiliation(s)
- Min-Chih Cheng
- Department of Psychiatry, Yuli Branch, Taipei Veterans General Hospital, Hualien 981, Taiwan;
| | - Wei-Hsien Chien
- Department of Occupational Therapy, College of Medicine, Fu Jen Catholic University, New Taipei City 242, Taiwan;
| | - Yu-Shu Huang
- Department of Psychiatry, Chang Gung Memorial Hospital-Linkou, Taoyuan 333, Taiwan;
- School of Medicine, College of Medicine, Chang Gung University, Taoyuan 333, Taiwan;
| | - Ting-Hsuan Fang
- School of Medicine, College of Medicine, Chang Gung University, Taoyuan 333, Taiwan;
| | - Chia-Hsiang Chen
- Department of Psychiatry, Chang Gung Memorial Hospital-Linkou, Taoyuan 333, Taiwan;
- Department and Institute of Biomedical Sciences, Chang Gung University, Taoyuan 333, Taiwan
- Correspondence:
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11
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Zhao Y, Li J, Dai L, Ma Y, Bai Y, Guo H. X Chromosome Inactivation Pattern and Pregnancy Outcome of Female Carriers of Pathogenic Heterozygous X-Linked Deletions. Front Genet 2021; 12:782629. [PMID: 34976017 PMCID: PMC8719196 DOI: 10.3389/fgene.2021.782629] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Accepted: 11/22/2021] [Indexed: 11/13/2022] Open
Abstract
Prenatal risk assessment of carriers of heterozygous X-linked deletion is a big challenge due to the phenotypic modification induced by X chromosome inactivation (XCI). Herein, we described four Chinese pedigrees with maternal-inherited X-deletions above 1 Mb. The pathogenic evaluation revealed that all X-deletions are harmful to heterozygous carriers; however, the asymptomatic pregnant female carriers in these families tremendously complicate the prognostic assessment of the unborn heterozygous embryos. In this study, we detected the XCI pattern of 11 female carriers of heterozygous X-linked deletions and 4 non-carrier females in these families and performed the first prenatal XCI pattern analysis in a fetal female carrier of heterozygous PCDH19-deletion to make risk prediction. In an adult female who lost one copy of the terminal of X chromosome short arm (Xp), a region enriching a large number of XCI escapees, the expression level of representative XCI escape genes was also detected. Pregnancy outcomes of all families were followed up or retrospected. Our research provides clinical evidence that X-deletions above 1 Mb are indeed associated with extremely skewed XCI. The favorable skewed XCI in combination with potential compensatory upregulation of XCI escapees would protect some but not all female carriers with pathogenic X-deletion from severe clinical consequences, mainly depending on the specific genetic contents involved in the deletion region. For PCDH19-disorder, the XCI pattern is considered as the decisive factor of phenotype expression, of which prenatal XCI assay using uncultured amniocytes could be a practicable way for risk prediction of this disease. These results provide valuable information about the usage of XCI assay in the prenatal risk assessment of heterozygous X-linked deletions.
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Affiliation(s)
- Yuanyin Zhao
- Department of Medical Genetics, College of Basic Medical Science, Army Medical University, Chongqing, China
- Department of Biochemistry and Molecular Biology, College of Basic Medical Science, Army Medical University, Chongqing, China
| | - Jia Li
- Department of Medical Genetics, College of Basic Medical Science, Army Medical University, Chongqing, China
| | - Limeng Dai
- Department of Medical Genetics, College of Basic Medical Science, Army Medical University, Chongqing, China
| | - Yongyi Ma
- Department of Gynaecology and Obstetrics, Southwest Hospital, Army Medical University, Chongqing, China
| | - Yun Bai
- Department of Medical Genetics, College of Basic Medical Science, Army Medical University, Chongqing, China
| | - Hong Guo
- Department of Medical Genetics, College of Basic Medical Science, Army Medical University, Chongqing, China
- Department of Gynaecology and Obstetrics, Xinqiao Hospital, Army Medical University, Chongqing, China
- *Correspondence: Hong Guo,
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12
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De La Vega FM, Chowdhury S, Moore B, Frise E, McCarthy J, Hernandez EJ, Wong T, James K, Guidugli L, Agrawal PB, Genetti CA, Brownstein CA, Beggs AH, Löscher BS, Franke A, Boone B, Levy SE, Õunap K, Pajusalu S, Huentelman M, Ramsey K, Naymik M, Narayanan V, Veeraraghavan N, Billings P, Reese MG, Yandell M, Kingsmore SF. Artificial intelligence enables comprehensive genome interpretation and nomination of candidate diagnoses for rare genetic diseases. Genome Med 2021; 13:153. [PMID: 34645491 PMCID: PMC8515723 DOI: 10.1186/s13073-021-00965-0] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Accepted: 08/27/2021] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Clinical interpretation of genetic variants in the context of the patient's phenotype is becoming the largest component of cost and time expenditure for genome-based diagnosis of rare genetic diseases. Artificial intelligence (AI) holds promise to greatly simplify and speed genome interpretation by integrating predictive methods with the growing knowledge of genetic disease. Here we assess the diagnostic performance of Fabric GEM, a new, AI-based, clinical decision support tool for expediting genome interpretation. METHODS We benchmarked GEM in a retrospective cohort of 119 probands, mostly NICU infants, diagnosed with rare genetic diseases, who received whole-genome or whole-exome sequencing (WGS, WES). We replicated our analyses in a separate cohort of 60 cases collected from five academic medical centers. For comparison, we also analyzed these cases with current state-of-the-art variant prioritization tools. Included in the comparisons were trio, duo, and singleton cases. Variants underpinning diagnoses spanned diverse modes of inheritance and types, including structural variants (SVs). Patient phenotypes were extracted from clinical notes by two means: manually and using an automated clinical natural language processing (CNLP) tool. Finally, 14 previously unsolved cases were reanalyzed. RESULTS GEM ranked over 90% of the causal genes among the top or second candidate and prioritized for review a median of 3 candidate genes per case, using either manually curated or CNLP-derived phenotype descriptions. Ranking of trios and duos was unchanged when analyzed as singletons. In 17 of 20 cases with diagnostic SVs, GEM identified the causal SVs as the top candidate and in 19/20 within the top five, irrespective of whether SV calls were provided or inferred ab initio by GEM using its own internal SV detection algorithm. GEM showed similar performance in absence of parental genotypes. Analysis of 14 previously unsolved cases resulted in a novel finding for one case, candidates ultimately not advanced upon manual review for 3 cases, and no new findings for 10 cases. CONCLUSIONS GEM enabled diagnostic interpretation inclusive of all variant types through automated nomination of a very short list of candidate genes and disorders for final review and reporting. In combination with deep phenotyping by CNLP, GEM enables substantial automation of genetic disease diagnosis, potentially decreasing cost and expediting case review.
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Affiliation(s)
- Francisco M. De La Vega
- Fabric Genomics Inc., Oakland, CA USA
- Department of Biomedical Data Science, Stanford University School of Medicine, Stanford, CA USA
- Current Address: Tempus Labs Inc., Redwood City, CA 94065 USA
| | - Shimul Chowdhury
- Rady Children’s Institute for Genomic Medicine, San Diego, CA USA
| | - Barry Moore
- Department of Human Genetics, Utah Center for Genetic Discovery, University of Utah, Salt Lake City, UT USA
| | | | | | - Edgar Javier Hernandez
- Department of Human Genetics, Utah Center for Genetic Discovery, University of Utah, Salt Lake City, UT USA
| | - Terence Wong
- Rady Children’s Institute for Genomic Medicine, San Diego, CA USA
| | - Kiely James
- Rady Children’s Institute for Genomic Medicine, San Diego, CA USA
| | - Lucia Guidugli
- Rady Children’s Institute for Genomic Medicine, San Diego, CA USA
| | - Pankaj B. Agrawal
- Division of Genetics and Genomics, The Manton Center for Orphan Disease Research, Boston Children’s Hospital, Harvard Medical School, Boston, MA USA
- Division of Newborn Medicine, Boston Children’s Hospital, Boston, MA USA
| | - Casie A. Genetti
- Division of Genetics and Genomics, The Manton Center for Orphan Disease Research, Boston Children’s Hospital, Harvard Medical School, Boston, MA USA
| | - Catherine A. Brownstein
- Division of Genetics and Genomics, The Manton Center for Orphan Disease Research, Boston Children’s Hospital, Harvard Medical School, Boston, MA USA
| | - Alan H. Beggs
- Division of Genetics and Genomics, The Manton Center for Orphan Disease Research, Boston Children’s Hospital, Harvard Medical School, Boston, MA USA
| | - Britt-Sabina Löscher
- Institute of Clinical Molecular Biology, Christian-Albrechts-University of Kiel & University Hospital Schleswig-Holstein, Kiel, Germany
| | - Andre Franke
- Institute of Clinical Molecular Biology, Christian-Albrechts-University of Kiel & University Hospital Schleswig-Holstein, Kiel, Germany
| | - Braden Boone
- HudsonAlpha Institute for Biotechnology, Huntsville, AL USA
| | - Shawn E. Levy
- HudsonAlpha Institute for Biotechnology, Huntsville, AL USA
| | - Katrin Õunap
- Department of Clinical Genetics, United Laboratories, Tartu University Hospital, Tartu, Estonia
- Department of Clinical Genetics, Institute of Clinical Medicine, University of Tartu, Tartu, Estonia
| | - Sander Pajusalu
- Department of Clinical Genetics, United Laboratories, Tartu University Hospital, Tartu, Estonia
- Department of Clinical Genetics, Institute of Clinical Medicine, University of Tartu, Tartu, Estonia
| | - Matt Huentelman
- Center for Rare Childhood Disorders, Translational Genomics Research Institute, Phoenix, AZ USA
| | - Keri Ramsey
- Center for Rare Childhood Disorders, Translational Genomics Research Institute, Phoenix, AZ USA
| | - Marcus Naymik
- Center for Rare Childhood Disorders, Translational Genomics Research Institute, Phoenix, AZ USA
| | - Vinodh Narayanan
- Center for Rare Childhood Disorders, Translational Genomics Research Institute, Phoenix, AZ USA
| | | | | | | | - Mark Yandell
- Fabric Genomics Inc., Oakland, CA USA
- Department of Human Genetics, Utah Center for Genetic Discovery, University of Utah, Salt Lake City, UT USA
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13
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Dai L, Zhang D, Wu Z, Guan X, Ma M, Li L, Zhang Y, Bai Y, Guo H. A Tiered Genetic Screening Strategy for the Molecular Diagnosis of Intellectual Disability in Chinese Patients. Front Genet 2021; 12:669217. [PMID: 34630504 PMCID: PMC8495063 DOI: 10.3389/fgene.2021.669217] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Accepted: 09/10/2021] [Indexed: 01/02/2023] Open
Abstract
Objective: Intellectual disability (ID) is one of the most common developmental disabilities. To identify the genetic etiology of IDs in Chongqing, we conducted a multistage study in Chinese Han patients. Methods: We collected the clinical and etiological data of 1665 ID patients, including 1,604 from the disabled children evaluation center and 61 from the pediatric rehabilitation unit. Routine genetic screening results were obtained, including karyotype and candidate gene analysis. Then 105 idiopathic cases with syndromic and severe ID/developmental delay (DD) were selected and tested by chromosomal microarray (CMA) and whole exome sequencing (WES) sequentially. The pathogenicity of the CNVs and SNVs were evaluated according to ACMG guidelines. Results: Molecular diagnosis was made by routine genetic screening in 216 patients, including 196 chromosomal syndromes. Among the 105 idiopathic patients, 49 patients with pathogenic/likely pathogenic CNVs and 21 patients with VUS were identified by CMA. Twenty-six pathogenic CNVs underlying well-known syndromic cases, such as Williams-Beuren syndrome, were confirmed by multiplex ligation-dependent probe amplification (MLPA). Nine novel mutations were identified by WES in thirty-fix CNV-negative ID cases. Conclusions: The study illustrated the genetic aberrations distribution of a large ID cohort in Chongqing. Compared with conventional or single methods, a tiered high-throughput diagnostic strategy was developed to greatly improve the diagnostic yields and extend the variation spectrum for idiopathic syndromic ID cases.
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Affiliation(s)
- Limeng Dai
- Department of Medical Genetics, College of Basic Medical Science, Army Medical University, Chongqing, China
| | - Danyan Zhang
- Department of Medical Genetics, College of Basic Medical Science, Army Medical University, Chongqing, China.,Chongqing Population and Family Planning Science and Technology Research Institute/NHC Key Laboratory of Birth Defects and Reproductive Health, Chongqing, China
| | - Zhifeng Wu
- Department of Pediatrics, Xinqiao Hospital, Army Medical University, Chongqing, China
| | - Xingying Guan
- Department of Medical Genetics, College of Basic Medical Science, Army Medical University, Chongqing, China
| | - Mingfu Ma
- Chongqing Population and Family Planning Science and Technology Research Institute/NHC Key Laboratory of Birth Defects and Reproductive Health, Chongqing, China
| | - Lianbing Li
- Chongqing Population and Family Planning Science and Technology Research Institute/NHC Key Laboratory of Birth Defects and Reproductive Health, Chongqing, China
| | - Yuping Zhang
- Department of Pediatrics, Xinqiao Hospital, Army Medical University, Chongqing, China
| | - Yun Bai
- Department of Medical Genetics, College of Basic Medical Science, Army Medical University, Chongqing, China
| | - Hong Guo
- Department of Medical Genetics, College of Basic Medical Science, Army Medical University, Chongqing, China
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14
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The Polygenic Nature and Complex Genetic Architecture of Specific Learning Disorder. Brain Sci 2021; 11:brainsci11050631. [PMID: 34068951 PMCID: PMC8156942 DOI: 10.3390/brainsci11050631] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 05/11/2021] [Accepted: 05/12/2021] [Indexed: 12/16/2022] Open
Abstract
Specific Learning Disorder (SLD) is a multifactorial, neurodevelopmental disorder which may involve persistent difficulties in reading (dyslexia), written expression and/or mathematics. Dyslexia is characterized by difficulties with speed and accuracy of word reading, deficient decoding abilities, and poor spelling. Several studies from different, but complementary, scientific disciplines have investigated possible causal/risk factors for SLD. Biological, neurological, hereditary, cognitive, linguistic-phonological, developmental and environmental factors have been incriminated. Despite worldwide agreement that SLD is highly heritable, its exact biological basis remains elusive. We herein present: (a) an update of studies that have shaped our current knowledge on the disorder’s genetic architecture; (b) a discussion on whether this genetic architecture is ‘unique’ to SLD or, alternatively, whether there is an underlying common genetic background with other neurodevelopmental disorders; and, (c) a brief discussion on whether we are at a position of generating meaningful correlations between genetic findings and anatomical data from neuroimaging studies or specific molecular/cellular pathways. We conclude with open research questions that could drive future research directions.
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