Abstract:Objective: To investigate the pathogenesis gene in a family with autosomal dominant congenital cataracts (ADCC) by target rejoin capture sequencing. Methods: A three-generations Chinese family with ADCC were recruited and all patients underwent comprehensive ophthalmic examinations. Target rejoin capture sequencing was performed on the proband, then the sequencing results were compared with the data of human genomic database, the synonymous mutation was filled after reported common variants. Sanger sequencing was used to validate co-segregation of the candidate variant in the family. The impact on the amino acid sequences and the conservation of the variant were further analyzed. Results: Seven patients were found in this family, the patients were distributed in each generation with equal incidence rates in male and female subjects. Target rejoin capture sequencing found a heterozygous mutation c.1532C>T (p.T511M) in EPHA2(ephrin typeA receptor2), which was highly conserved among various species and resulted in an abnormal EPHA2 protein. Then the Sanger sequencing showed co-segregation of the mutation in the family. Conclusion: EPHA2 gene c.1532C>T (p.T511M) may be a pathogenic mutation in the family of congenital cataract.
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