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Gao B, Jiang Y, Han M, Ji X, Zhang D, Wu L, Gao X, Huang S, Zhao C, Su Y, Yang S, Zhang X, Liu N, Han L, Wang L, Ren L, Yang J, Wu J, Yuan Y, Dai P. Targeted Linked-Read Sequencing for Direct Haplotype Phasing of Parental GJB2/SLC26A4 Alleles: A Universal and Dependable Noninvasive Prenatal Diagnosis Method Applied to Autosomal Recessive Nonsyndromic Hearing Loss in At-Risk Families. J Mol Diagn 2024; 26:638-651. [PMID: 38663495 DOI: 10.1016/j.jmoldx.2024.04.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Revised: 03/04/2024] [Accepted: 04/10/2024] [Indexed: 05/04/2024] Open
Abstract
Noninvasive prenatal diagnosis (NIPD) for autosomal recessive nonsyndromic hearing loss (ARNSHL) has been rarely reported until recent years. Additionally, the existing method can not be used for challenging genome loci (eg, copy number variations, deletions, inversions, or gene recombinants) or on families without proband genotype. This study assessed the performance of relative haplotype dosage analysis (RHDO)-based NIPD for identifying fetal genotyping in pregnancies at risk of ARNSHL. Fifty couples carrying pathogenic variants associated with ARNSHL in either GJB2 or SLC26A4 were recruited. The RHDO-based targeted linked-read sequencing combined with whole gene coverage probes was used to genotype the fetal cell-free DNA of 49 families who met the quality control standard. Fetal amniocyte samples were genotyped using invasive prenatal diagnosis (IPD) to assess the performance of NIPD. The NIPD results showed 100% (49/49) concordance with those obtained through IPD. Two families with copy number variation and recombination were also successfully identified. Sufficient specific informative single-nucleotide polymorphisms for haplotyping, as well as the fetal cell-free DNA concentration and sequencing depth, are prerequisites for RHDO-based NIPD. This method has the merits of covering the entire genes of GJB2 and SLC26A4, qualifying for copy number variation and recombination analysis with remarkable sensitivity and specificity. Therefore, it has clinical potential as an alternative to traditional IPD for ARNSHL.
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Affiliation(s)
- Bo Gao
- Senior Department of Otolaryngology Head and Neck Surgery, The 6th Medical Center of Chinese PLA General Hospital, Chinese PLA Medical School, Beijing, China; State Key Laboratory of Hearing and Balance Science, Beijing, China; National Clinical Research Center for Otolaryngologic Diseases, Beijing, China; Key Laboratory of Hearing Science, Ministry of Education, Beijing, China; Beijing Key Laboratory of Hearing Impairment Prevention and Treatment, Beijing, China
| | - Yi Jiang
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Ear Institute, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai, China
| | - Mingyu Han
- Senior Department of Otolaryngology Head and Neck Surgery, The 6th Medical Center of Chinese PLA General Hospital, Chinese PLA Medical School, Beijing, China; State Key Laboratory of Hearing and Balance Science, Beijing, China; National Clinical Research Center for Otolaryngologic Diseases, Beijing, China; Key Laboratory of Hearing Science, Ministry of Education, Beijing, China; Beijing Key Laboratory of Hearing Impairment Prevention and Treatment, Beijing, China
| | | | - Dejun Zhang
- Senior Department of Otolaryngology Head and Neck Surgery, The 6th Medical Center of Chinese PLA General Hospital, Chinese PLA Medical School, Beijing, China; State Key Laboratory of Hearing and Balance Science, Beijing, China; National Clinical Research Center for Otolaryngologic Diseases, Beijing, China; Key Laboratory of Hearing Science, Ministry of Education, Beijing, China; Beijing Key Laboratory of Hearing Impairment Prevention and Treatment, Beijing, China
| | - Lihua Wu
- Department of Otolaryngology, Fujian Medical University ShengLi Clinical College, Fujian Provincial Hospital, Fuzhou, China
| | - Xue Gao
- Department of Otolaryngology, PLA Rocket Force Characteristic Medical Center, Beijing, China
| | - Shasha Huang
- Senior Department of Otolaryngology Head and Neck Surgery, The 6th Medical Center of Chinese PLA General Hospital, Chinese PLA Medical School, Beijing, China; State Key Laboratory of Hearing and Balance Science, Beijing, China; National Clinical Research Center for Otolaryngologic Diseases, Beijing, China; Key Laboratory of Hearing Science, Ministry of Education, Beijing, China; Beijing Key Laboratory of Hearing Impairment Prevention and Treatment, Beijing, China
| | - Chaoyue Zhao
- Senior Department of Otolaryngology Head and Neck Surgery, The 6th Medical Center of Chinese PLA General Hospital, Chinese PLA Medical School, Beijing, China; State Key Laboratory of Hearing and Balance Science, Beijing, China; National Clinical Research Center for Otolaryngologic Diseases, Beijing, China; Key Laboratory of Hearing Science, Ministry of Education, Beijing, China; Beijing Key Laboratory of Hearing Impairment Prevention and Treatment, Beijing, China
| | - Yu Su
- Senior Department of Otolaryngology Head and Neck Surgery, The 6th Medical Center of Chinese PLA General Hospital, Chinese PLA Medical School, Beijing, China; State Key Laboratory of Hearing and Balance Science, Beijing, China; National Clinical Research Center for Otolaryngologic Diseases, Beijing, China; Key Laboratory of Hearing Science, Ministry of Education, Beijing, China; Beijing Key Laboratory of Hearing Impairment Prevention and Treatment, Beijing, China
| | - Suyan Yang
- Senior Department of Otolaryngology Head and Neck Surgery, The 6th Medical Center of Chinese PLA General Hospital, Chinese PLA Medical School, Beijing, China; State Key Laboratory of Hearing and Balance Science, Beijing, China; National Clinical Research Center for Otolaryngologic Diseases, Beijing, China; Key Laboratory of Hearing Science, Ministry of Education, Beijing, China; Beijing Key Laboratory of Hearing Impairment Prevention and Treatment, Beijing, China
| | - Xin Zhang
- Senior Department of Otolaryngology Head and Neck Surgery, The 6th Medical Center of Chinese PLA General Hospital, Chinese PLA Medical School, Beijing, China; State Key Laboratory of Hearing and Balance Science, Beijing, China; National Clinical Research Center for Otolaryngologic Diseases, Beijing, China; Key Laboratory of Hearing Science, Ministry of Education, Beijing, China; Beijing Key Laboratory of Hearing Impairment Prevention and Treatment, Beijing, China
| | - Na Liu
- MyGenostics Inc., Beijing, China
| | - Lu Han
- MyGenostics Inc., Beijing, China
| | | | - Lina Ren
- MyGenostics Inc., Beijing, China
| | - Jinyuan Yang
- Senior Department of Otolaryngology Head and Neck Surgery, The 6th Medical Center of Chinese PLA General Hospital, Chinese PLA Medical School, Beijing, China; State Key Laboratory of Hearing and Balance Science, Beijing, China; National Clinical Research Center for Otolaryngologic Diseases, Beijing, China; Key Laboratory of Hearing Science, Ministry of Education, Beijing, China; Beijing Key Laboratory of Hearing Impairment Prevention and Treatment, Beijing, China
| | - Jian Wu
- MyGenostics Inc., Beijing, China
| | - Yongyi Yuan
- Senior Department of Otolaryngology Head and Neck Surgery, The 6th Medical Center of Chinese PLA General Hospital, Chinese PLA Medical School, Beijing, China; State Key Laboratory of Hearing and Balance Science, Beijing, China; National Clinical Research Center for Otolaryngologic Diseases, Beijing, China; Key Laboratory of Hearing Science, Ministry of Education, Beijing, China; Beijing Key Laboratory of Hearing Impairment Prevention and Treatment, Beijing, China.
| | - Pu Dai
- Senior Department of Otolaryngology Head and Neck Surgery, The 6th Medical Center of Chinese PLA General Hospital, Chinese PLA Medical School, Beijing, China; State Key Laboratory of Hearing and Balance Science, Beijing, China; National Clinical Research Center for Otolaryngologic Diseases, Beijing, China; Key Laboratory of Hearing Science, Ministry of Education, Beijing, China; Beijing Key Laboratory of Hearing Impairment Prevention and Treatment, Beijing, China.
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Lin Q, Liang C, Du B, Li L, Li H, Mai X, Li S, Xu W, Wu C, Zeng M. Prenatal detection and molecular cytogenetic characterization of Xp deletion and Xq duplication: a case report and literature review. BMC Med Genomics 2024; 17:57. [PMID: 38383389 PMCID: PMC10880359 DOI: 10.1186/s12920-024-01824-8] [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: 10/31/2023] [Accepted: 02/06/2024] [Indexed: 02/23/2024] Open
Abstract
BACKGROUND Copy number variation (CNV) of X chromosome can lead to a variety of neonatal abnormalities, especially for male fetuses. In recent years, due to the high sensitivity and high specificity of NIPS, its application has gradually expanded from chromosome aneuploidy to CNV. Few prenatal cases involving the detection of Xq duplication and deletion by NIPS have been reported, but it is of great significance for genetic counseling. CASE PRESENTATION A 36-year-old woman was referred for prenatal diagnosis and genetic counseling at 17 weeks of gestation because of abnormal result of noninvasive prenatal screening (NIPS). Multiple congenital malformations, hydrocephalus, and enlarged gallbladder were observed by prenatal ultrasound. Amniocentesis revealed the karyotype of the fetus as 46, XN, add(X) (p22.2) and the result of chromosomal microarray analysis was arr[hg19] Xq27.1q28(138,506,454-154896094) × 2 and arr[hg19] Xp22.33p22.32(168,551-5,616,964) × 1. CNV-seq showed that the mother shares a 16.42 Mb duplication in the Xq27.1-q28 region and a 2.97 Mb deletion in the Xp22.33-p22.32 region. After genetic counseling, the couple chose to terminate the pregnancy. CONCLUSION The combination of NIPS and CMA would be of values in detection of subchromosomal duplications and/or deletions at fetal stage. The detection of X chromosome aberration in a male fetus should give suspicion of the possibility of maternal inheritance.
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Affiliation(s)
- Qing Lin
- Center of Prenatal Diagnosis, Zhanjiang Maternity and Child Health Care Hospital, Zhanjiang, China.
| | - Chunya Liang
- Center of Prenatal Diagnosis, Zhanjiang Maternity and Child Health Care Hospital, Zhanjiang, China
| | - Bole Du
- Guangzhou Jingke Biotechnology Co., Ltd, Guangzhou, P. R. China
| | - Lijiao Li
- Center of Prenatal Diagnosis, Zhanjiang Maternity and Child Health Care Hospital, Zhanjiang, China
| | - Hong Li
- Guangzhou Jingke Biotechnology Co., Ltd, Guangzhou, P. R. China
| | - Xiaolan Mai
- Center of Prenatal Diagnosis, Zhanjiang Maternity and Child Health Care Hospital, Zhanjiang, China
| | - Sheng Li
- Guangzhou Jingke Biotechnology Co., Ltd, Guangzhou, P. R. China
| | - Wenyu Xu
- Center of Prenatal Diagnosis, Zhanjiang Maternity and Child Health Care Hospital, Zhanjiang, China
| | - Cunzhen Wu
- Center of Prenatal Diagnosis, Zhanjiang Maternity and Child Health Care Hospital, Zhanjiang, China
| | - Mi Zeng
- Guangzhou Jingke Biotechnology Co., Ltd, Guangzhou, P. R. China
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Cai M, Lin N, Guo N, Su L, Wu X, Xie X, Li Y, He S, Fu X, Xu L, Huang H. Using single nucleotide polymorphism array for prenatal diagnosis in a large multicenter study in Southern China. Sci Rep 2023; 13:7242. [PMID: 37142625 PMCID: PMC10160013 DOI: 10.1038/s41598-023-33668-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Accepted: 04/17/2023] [Indexed: 05/06/2023] Open
Abstract
Numerous studies have evaluated the use of single nucleotide polymorphism array (SNP-array) in prenatal diagnostics, but very few have evaluated its application under different risk conditions. Here, SNP-array was used for the retrospective analysis of 8386 pregnancies and the cases were categorized into seven groups. Pathogenic copy number variations (pCNVs) were found in 699 (8.3%, 699/8386) cases. Among the seven different risk factor groups, the non-invasive prenatal testing-positive group had the highest pCNVs rate (35.3%), followed by the abnormal ultrasound structure group (12.8%), and then the chromosomal abnormalities in the couples group (9.5%). Notably the adverse pregnancy history group presented with the lowest pCNVs rate (2.8%). Further evaluation of the 1495 cases with ultrasound abnormalities revealed that the highest pCNV rates were recorded in those cases with multiple system structure abnormalities (22.6%), followed by the groups with skeletal system (11.6%) and urinary system abnormalities (11.2%). A total of 3424 fetuses with ultrasonic soft markers were classified as having one, two, or three ultrasonic soft markers. The different pCNV rates in the three groups were statistically significant. There was little correlation between pCNVs and a previous history of adverse pregnancy outcomes, suggesting that genetic screening under these conditions should be evaluated on a case-by-case basis.
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Affiliation(s)
- Meiying Cai
- Medical Genetic Diagnosis and Therapy Center, Fujian Maternity and Child Health Hospital College of Clinical Medicine for Obstetrics & Gynecology and Pediatrics, Fujian Medical University, Fujian Key Laboratory for Prenatal Diagnosis and Birth Defect, Fuzhou, China
| | - Na Lin
- Medical Genetic Diagnosis and Therapy Center, Fujian Maternity and Child Health Hospital College of Clinical Medicine for Obstetrics & Gynecology and Pediatrics, Fujian Medical University, Fujian Key Laboratory for Prenatal Diagnosis and Birth Defect, Fuzhou, China
| | - Nan Guo
- Medical Genetic Diagnosis and Therapy Center, Fujian Maternity and Child Health Hospital College of Clinical Medicine for Obstetrics & Gynecology and Pediatrics, Fujian Medical University, Fujian Key Laboratory for Prenatal Diagnosis and Birth Defect, Fuzhou, China
| | - Linjuan Su
- Medical Genetic Diagnosis and Therapy Center, Fujian Maternity and Child Health Hospital College of Clinical Medicine for Obstetrics & Gynecology and Pediatrics, Fujian Medical University, Fujian Key Laboratory for Prenatal Diagnosis and Birth Defect, Fuzhou, China
| | - Xiaoqing Wu
- Medical Genetic Diagnosis and Therapy Center, Fujian Maternity and Child Health Hospital College of Clinical Medicine for Obstetrics & Gynecology and Pediatrics, Fujian Medical University, Fujian Key Laboratory for Prenatal Diagnosis and Birth Defect, Fuzhou, China
| | - Xiaorui Xie
- Medical Genetic Diagnosis and Therapy Center, Fujian Maternity and Child Health Hospital College of Clinical Medicine for Obstetrics & Gynecology and Pediatrics, Fujian Medical University, Fujian Key Laboratory for Prenatal Diagnosis and Birth Defect, Fuzhou, China
| | - Ying Li
- Medical Genetic Diagnosis and Therapy Center, Fujian Maternity and Child Health Hospital College of Clinical Medicine for Obstetrics & Gynecology and Pediatrics, Fujian Medical University, Fujian Key Laboratory for Prenatal Diagnosis and Birth Defect, Fuzhou, China
| | - Shuqiong He
- Medical Genetic Diagnosis and Therapy Center, Fujian Maternity and Child Health Hospital College of Clinical Medicine for Obstetrics & Gynecology and Pediatrics, Fujian Medical University, Fujian Key Laboratory for Prenatal Diagnosis and Birth Defect, Fuzhou, China
| | - Xianguo Fu
- Department of Prenatal Diagnosis, Ningde Municipal Hospital, Ningde Normal University, Ningde, China.
| | - Liangpu Xu
- Medical Genetic Diagnosis and Therapy Center, Fujian Maternity and Child Health Hospital College of Clinical Medicine for Obstetrics & Gynecology and Pediatrics, Fujian Medical University, Fujian Key Laboratory for Prenatal Diagnosis and Birth Defect, Fuzhou, China.
| | - Hailong Huang
- Medical Genetic Diagnosis and Therapy Center, Fujian Maternity and Child Health Hospital College of Clinical Medicine for Obstetrics & Gynecology and Pediatrics, Fujian Medical University, Fujian Key Laboratory for Prenatal Diagnosis and Birth Defect, Fuzhou, China.
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Bunyan DJ, Hobbs JI, Duncan-Flavell PJ, Howarth RJ, Beal S, Baralle D, Thomas NS. SHOX Whole Gene Duplications Are Overrepresented in SHOX Haploinsufficiency Phenotype Cohorts. Cytogenet Genome Res 2023; 162:587-598. [PMID: 36927524 DOI: 10.1159/000530171] [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: 12/19/2022] [Accepted: 03/13/2023] [Indexed: 03/18/2023] Open
Abstract
Transcription of SHOX is dependent upon the interaction of the gene with a complex array of flanking regulatory elements. Duplications that contain flanking regulatory elements but not the SHOX gene have been reported in individuals with SHOX haploinsufficiency syndromes, suggesting that alterations to the physical organisation or genomic architecture may affect SHOX transcription. Individuals with tall stature and an additional X or Y chromosome have an extra copy of both the SHOX gene and the entire SHOX regulatory region, so all three copies of SHOX can be expressed fully. However, for a duplication of the SHOX gene that does not include all of the flanking regulatory elements, the potential effect on SHOX expression is difficult to predict. We present nine unpublished individuals with a SHOX whole gene duplication in whom the duplication contains variable amounts of the SHOX regulatory region, and we review 29 similar cases from the literature where phenotypic data were clearly stated. While tall stature was present in a proportion of these cases, we present evidence that SHOX whole gene duplications can also result in a phenotype more typically associated with SHOX haploinsufficiency and are significantly overrepresented in Leri-Weill dyschondrosteosis and idiopathic short stature probands compared to population controls. Although similar-looking duplications do not always produce a consistent phenotype, there may be potential genotype-phenotype correlations regarding the duplication size, regulatory element content, and the breakpoint proximity to the SHOX gene. Although ClinGen does not currently consider SHOX whole gene duplications to be clinically significant, the ClinGen triplosensitivity score does not take into account the context of the duplication, and more is now known about SHOX duplications and the role of flanking elements in SHOX regulation. The evidence presented here suggests that these duplications should not be discounted without considering the extent of the duplication and the patient phenotype, and should be included in diagnostic laboratory reports as variants of uncertain significance. Given the uncertain pathogenicity of these duplications, any reports should encourage the exclusion of all other causes of short stature where possible.
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Affiliation(s)
- David J Bunyan
- Wessex Genomics Laboratory Service, Salisbury District Hospital, Salisbury, UK
- Human Development and Health, Faculty of Medicine, University of Southampton, Southampton, UK
| | - James I Hobbs
- Wessex Genomics Laboratory Service, Salisbury District Hospital, Salisbury, UK
| | | | - Rachel J Howarth
- Wessex Genomics Laboratory Service, Salisbury District Hospital, Salisbury, UK
| | - Sarah Beal
- Wessex Genomics Laboratory Service, Salisbury District Hospital, Salisbury, UK
| | - Diana Baralle
- Human Development and Health, Faculty of Medicine, University of Southampton, Southampton, UK
- Wessex Clinical Genetics Service, University Hospital Southampton NHS Foundation Trust, Southampton, UK
| | - Nicholas Simon Thomas
- Wessex Genomics Laboratory Service, Salisbury District Hospital, Salisbury, UK
- Human Development and Health, Faculty of Medicine, University of Southampton, Southampton, UK
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Shi B, Ye Y. Case report: A reciprocal translocation-free and pathogenic DUOX2 mutation-free embryo selected by complicated preimplantation genetic testing resulted in a healthy live birth. Front Genet 2023; 14:1066199. [PMID: 36873947 PMCID: PMC9982009 DOI: 10.3389/fgene.2023.1066199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Accepted: 02/06/2023] [Indexed: 02/19/2023] Open
Abstract
Preimplantation genetic testing (PGT) is an effective approach to improve clinical outcomes and prevent transmission of genetic imbalances by selecting embryos free of disease-causing genes and chromosome abnormalities. In this study, PGT was performed for a challenging case in which a couple simultaneously carried a maternal subchromosomal reciprocal translocation (RecT) revealed by fluorescence in situ hybridization involving the chromosome X (ChrX) and heterozygous mutations in dual oxidase 2 (DUOX2). Carriers of RecT are at increased risk for infertility, recurrent miscarriages, or having affected children due to the unbalanced gametes produced. DUOX2 mutation results in congenital hypothyroidism. Pedigree haplotypes for DUOX2 was constructed after the mutations were verified by Sanger sequencing. Since male carriers of X-autosome translocations may exhibit infertility or other abnormalities, pedigree haplotype for chromosomal translocation was also constructed to identify embryo with RecT. Three blastocysts were obtained by in vitro fertilization and underwent trophectoderm biopsy, whole genomic amplification, and next-generation sequencing (NGS). A blastocyst lacking copy number variants and RecT but carrying the paternal gene mutation in DUOX2, c.2654G>T (p.R885L) was used for embryo transfer, resulting in a healthy female infant whose genetic properties were confirmed by amniocentesis. Cases containing RecT and single gene disorder are rare. And the situation is more complicated when the subchromosomal RecT involving ChrX cannot be identified with routine karyotype analysis. This case report contributes significantly to the literature and the results have shown that the NGS-based PGT strategy may be broadly useful for complex pedigrees.
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Affiliation(s)
- Biwei Shi
- Department of Reproductive Endocrinology, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Yinghui Ye
- Department of Reproductive Endocrinology, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, China
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Shi Y, Li X, Ju D, Li Y, Zhang X, Zhang Y. Abnormal chromosomes identification using chromosomal microarray. J OBSTET GYNAECOL 2022; 42:2025-2032. [PMID: 35659171 DOI: 10.1080/01443615.2022.2074786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
In this study, we presented a case series to highlight the chromosomal microarray (CMA) in identifying chromosomal abnormalities which is undetectable by conventional karyotyping or known abnormal chromosomes without clear diagnosis. Extensive studies showed that CMA was gradually accepted as a prenatal invasive testing during pregnancy. The aim of this study was to evaluate the diagnostic effect of CMA for foetuses with abnormal chromosomes unrecognised by conventional karyotyping. Pregnant women who need prenatal diagnosis with all indications were enrolled in this study. For aberrant cytogenetic findings that cannot be defined by routine karyotyping, single nucleotide polymorphism array (SNP-array) was used. Six cases with abnormal karyotype were included in the study. With higher resolution of translocation breakpoints, CMA could detect smaller chromosomal imbalances that were undetectable by karyotyping. This study highlights the value of CMA for the detection of submicroscopic abnormalities in foetuses that cannot be detected by conventional karyotyping. Impact StatementWhat is already known on this subject? Chromosomal microarray (CMA) offers additional diagnostic benefits by revealing submicroscopic imbalances or copy number variations (CNVs) that are too small to be identified on a standard G-banded chromosome preparation.What do the results of this study add? We added a case series to highlight the CMA in identifying chromosomal abnormalities not detectable by conventional karyotyping or known abnormal chromosomes without clear diagnosis.What are the implications of these findings for clinical practice and/or further research? This study highlights the value of CMA in the case of associated foetuses with submicroscopic abnormalities that cannot detect by conventional karyotyping.
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Affiliation(s)
- Yunfang Shi
- Tianjin Medical University General Hospital, Tianjin, China
| | - Xiaozhou Li
- Tianjin Medical University General Hospital, Tianjin, China
| | - Duan Ju
- Tianjin Medical University General Hospital, Tianjin, China
| | - Yan Li
- Tianjin Medical University General Hospital, Tianjin, China
| | - Xiuling Zhang
- Tianjin Medical University General Hospital, Tianjin, China
| | - Ying Zhang
- Tianjin Medical University General Hospital, Tianjin, China
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LUO Y, SHEN M, SUN Y, QIAN Y, WANG L, YU J, HU J, JIN F, DONG M. [Genetic analysis of a fetus with multiple malformations caused by complex translocations of four chromosomes]. Zhejiang Da Xue Xue Bao Yi Xue Ban 2019; 48:397-402. [PMID: 31901043 PMCID: PMC8800750 DOI: 10.3785/j.issn.1008-9292.2019.08.08] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
OBJECTIVE To conduct genetic analysis in a fetus with complex translocation of four chromosomes. METHODS G-banded chromosome karyotype analysis, single nucleotide polymorphism array (SNP array) and fluorescence in situ hybridization (FISH) were performed in a fetus with multiple malformations. Peripheral blood chromosome karyotype and FISH were also carried out for the parents. RESULTS The fetal amniotic fluid karyotype was 46, XY, t(12; 13)(q22; q32). SNP array analysis showed that there were 20 192 kb duplication at 1q42.13q44 and 13 293 kb deletion at 15q26.1q26.3 in the fetus. The results of karyotype and SNP array were inconsistent. FISH analyses on the parental peripheral blood samples demonstrated that the mother was a cryptic 46, XX, t(1; 15)(q42.1; q26.1) translocation. The fetus had inherited 46, XY, t(12; 13)(q22; q32) from his father and der(15)t(1; 15)(q42.1; q26.1) from his mother. CONCLUSIONS The 1q42.13q44 duplication and 15q26.1q26.3 deletion may have contributed to the abnormal sonographic features of the fetus. The combination of cytogenetic, SNP array and FISH techniques was beneficial for providing an accurate genetic counseling.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Minyue DONG
- 董旻岳(1964—), 男, 博士, 主任医师, 博士生导师, 主要从事生殖遗传学研究; E-mail:
;
https://orcid.org/0000-0002-4344-7924
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Zepeda-Mendoza CJ, Morton CC. The Iceberg under Water: Unexplored Complexity of Chromoanagenesis in Congenital Disorders. Am J Hum Genet 2019; 104:565-577. [PMID: 30951674 DOI: 10.1016/j.ajhg.2019.02.024] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Accepted: 02/25/2019] [Indexed: 01/16/2023] Open
Abstract
Structural variation, composed of balanced and unbalanced genomic rearrangements, is an important contributor to human genetic diversity with prominent roles in somatic and congenital disease. At the nucleotide level, structural variants (SVs) have been shown to frequently harbor additional breakpoints and copy-number imbalances, a complexity predicted to emerge wholly as a single-cell division event. Chromothripsis, chromoplexy, and chromoanasynthesis, collectively referred to as chromoanagenesis, are three major mechanisms that explain the occurrence of complex germline and somatic SVs. While chromothripsis and chromoplexy have been shown to be key signatures of cancer, chromoanagenesis has been detected in numerous cases of developmental disease and phenotypically normal individuals. Such observations advocate for a deeper study of the polymorphic and pathogenic properties of complex germline SVs, many of which go undetected by traditional clinical molecular and cytogenetic methods. This review focuses on congenital chromoanagenesis, mechanisms leading to occurrence of these complex rearrangements, and their impact on chromosome organization and genome function. We highlight future applications of routine screening of complex and balanced SVs in the clinic, as these represent a potential and often neglected genetic disease source, a true "iceberg under water."
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Affiliation(s)
- Cinthya J Zepeda-Mendoza
- Division of Laboratory Genetics, Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN 55902, USA
| | - Cynthia C Morton
- Departments of Obstetrics and Gynecology and of Pathology, Brigham and Women's Hospital, Boston, MA 02115, USA; Harvard Medical School, Boston, MA 02115, USA; Program in Medical and Population Genetics, Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA; Manchester Center for Audiology and Deafness, School of Health Sciences, Manchester Academic Health Science Centre, University of Manchester, Manchester M13 9NT, UK.
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