A Novel Homozygous Loss-of-Function Variant in GPR156 Delineates Non-syndromic Hearing Loss.

Non-syndromic hearing loss (NSHL) is a genetically heterogeneous disorder accounting for almost 70% of the total congenital hearing loss. The implementation of rapid advanced sequencing methods has significantly contributed to the correct molecular diagnosis for several rare genetic disorders, including NHSL. Features of two probands with NHSL were clinically and genetically evaluated. One of the affected individuals was subjected to exome sequencing (ES) using standard methods. 3D protein modeling was performed to check the effect of mutation on the protein structure. ES data analysis revealed a homozygous nonsense variant [c.1144A > T; p.Lys382*] within the GPR156 gene (NM_153002.3) associated with rare NSHL. Sanger sequencing supported its recessive segregation within the family. The in silico predictions and 3D protein modeling further affirmed its disease-causing nature. The present study reported a nonsense variant in the GPR156 and its association with NSHL susceptibility, which requires further studies to unveil its key role and disease-related pathophysiology.