A Novel Exon 2 Deletion Mutation in the GRXCR1 Gene Associated With Non-Syndromic Hearing Loss: A Case Report and Review of Literatures

Abstract

Background: About 80% of congenital hearing loss cases have genetic causes, often autosomal recessive and non-syndromic. Autosomal Recessive Non-syndromic hearing loss is characterized by extreme genetic heterogeneity. Objectives: To report a case of congenital hearing loss with novel homozygous deletion in GRXCR1 gene. Methods: Case reports and review of literatures. Results: In this study, the proband was a 32-year-old woman seeking pre-marriage genetic counseling with non-syndromic congenital hearing loss. An owing negative test for GJB2 mutations, she underwent exome sequencing, unveiling a novel homozygous exon 2 deletion of the GRXCR1 gene. This mutation was confirmed in her affected mother and sibling by PCR and Quantitative Real-Time PCR. Conclusion: We identified a novel GRXCR1 gene mutation related to congenital hearing loss in a family. Our study highlights the efficiency of exome sequencing in discovering gene mutations in cases of diseases with genetic heterogeneity.