Dataset Information

Genetic spectrum and clinical features in a cohort of Chinese patients with autosomal recessive cerebellar ataxias.

ABSTRACT:

Background

Although many causative genes have been uncovered in recent years, genetic diagnosis is still missing for approximately 50% of autosomal recessive cerebellar ataxia (ARCA) patients. Few studies have been performed to determine the genetic spectrum and clinical profile of ARCA patients in the Chinese population.

Methods

Fifty-four Chinese index patients with unexplained autosomal recessive or sporadic ataxia were investigated by whole-exome sequencing (WES) and copy number variation (CNV) calling with ExomeDepth. Likely causal CNV predictions were validated by CNVseq.

Results

Thirty-eight mutations including 29 novel ones were identified in 25 out of the 54 patients, providing a 46.3% positive molecular diagnostic rate. Ten different genes were involved, of which four most common genes were SACS, SYNE1, ADCK3 and SETX, which accounted for 76.0% (19/25) of the positive cases. The de novo microdeletion in SACS was reported for the first time in China and the uniparental disomy of ADCK3 was reported for the first time worldwide. Clinical features of the patients carrying SACS, SYNE1 and ADCK3 mutations were summarized.

Conclusions

Our results expand the genetic spectrum and clinical profiles of ARCA patients, demonstrate the high efficiency and reliability of WES combined with CNV analysis in the diagnosis of suspected ARCA, and emphasize the importance of complete bioinformatics analysis of WES data for accurate diagnosis.

SUBMITTER: Cheng HL

PROVIDER: S-EPMC8522248 | biostudies-literature | 2021 Oct

REPOSITORIES: biostudies-literature

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Publications

Genetic spectrum and clinical features in a cohort of Chinese patients with autosomal recessive cerebellar ataxias.

Cheng Hao-Ling HL Shao Ya-Ru YR Dong Yi Y Dong Hai-Lin HL Yang Lu L Ma Yin Y Shen Ying Y Wu Zhi-Ying ZY

Translational neurodegeneration 20211018 1

<h4>Background</h4>Although many causative genes have been uncovered in recent years, genetic diagnosis is still missing for approximately 50% of autosomal recessive cerebellar ataxia (ARCA) patients. Few studies have been performed to determine the genetic spectrum and clinical profile of ARCA patients in the Chinese population.<h4>Methods</h4>Fifty-four Chinese index patients with unexplained autosomal recessive or sporadic ataxia were investigated by whole-exome sequencing (WES) and copy numb ...[more]

PMID: 34663476

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Dataset Information

Genetic spectrum and clinical features in a cohort of Chinese patients with autosomal recessive cerebellar ataxias.

Background

Methods

Results

Conclusions

Publications

Genetic spectrum and clinical features in a cohort of Chinese patients with autosomal recessive cerebellar ataxias.

Similar Datasets

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