Identification of de novo mutations for ARID1B haploinsufficiency associated with Coffin–Siris syndrome 1 in three Chinese families via array-CGH and whole exome sequencing

BMC Medical Genomics

Liya Ma¹  Qiongling Peng¹  Lianying Wu²  Guanting Lu²  Jian Zhang² 

[1] Department of Child Healthcare, Shenzhen Baoan Women’s and Children’s Hospital, Jinan University, 56 Yulyu Road, Baoan District, 518000, Shenzhen, China;Department of Pathology, Laboratory of Translational Medicine Research, Deyang Key Laboratory of Tumor Molecular Research, Deyang People’s Hospital, No. 173 First Section of TaishanBei Road, Jiangyang District, 618000, Deyang, China;

关键词: Haploinsufficiency;    ARID1B;    Coffin–Siris syndrome;    SWI/SNF complex;    Microdeletion;    Loss-of-function;   

DOI  :  10.1186/s12920-021-01119-2

来源: Springer

【 摘 要 】

BackgroundCoffin–Siris syndrome (CSS) is a multiple malformation syndrome characterized by intellectual disability associated with coarse facial features, hirsutism, sparse scalp hair, and hypoplastic or absent fifth fingernails or toenails. CSS represents a small group of intellectual disability, and could be caused by at least twelve genes. The genetic background is quite heterogenous, making it difficult for clinicians and genetic consultors to pinpoint the exact disease types.MethodsArray-Comparative Genomic Hybridization (array-CGH) and whole exome sequencing (WES) were applied for three trios affected with intellectual disability and clinical features similar with those of Coffin–Siris syndrome. Sanger sequencing was used to verify the detected single-nucleotide variants (SNVs).ResultsAll of the three cases were female with normal karyotypes of 46, XX, born of healthy, non-consanguineous parents. A 6q25 microdeletion (arr[hg19]6q25.3(155,966,487–158,803,979) × 1) (2.84 Mb) (case 1) and two loss-of-function (LoF) mutations of ARID1B [c.2332 + 1G > A in case 2 and c.4741C > T (p.Q1581X) in case 3] were identified. All of the three pathogenic abnormalities were de novo, not inherited from their parents. After comparison of publicly available microdeletions containing ARID1B, four types of microdeletions leading to insufficient production of ARID1B were identified, namely deletions covering the whole region of ARID1B, deletions covering the promoter region, deletions covering the termination region or deletions covering enhancer regions.ConclusionHere we identified de novo ARID1B mutations in three Chinese trios. Four types of microdeletions covering ARID1B were identified. This study broadens current knowledge of ARID1B mutations for clinicians and genetic consultors.

【 授权许可】

CC BY