A Novel p.G141R Mutation in ILDR1 Leads to Recessive Nonsyndromic Deafness DFNB42 in Two Chinese Han Families.

Xueling Wang,Longhao Wang,Tao Yang,Hu Peng,Hao Wu

doi:10.1155/2018/7272308

Abstract

Genetic hearing impairment is highly heterogeneous. In this study, targeted next-generation sequencing (NGS) in two Chinese Han families identified a novel p.G141R homozygous mutation in ILDR1 as the genetic cause of the deafness. Consistent with the recessive inheritance, cosegregation of the p.G141R variant with the hearing loss was confirmed in members of both families by PCR amplification and Sanger sequencing. SNP genotyping analysis suggested that those two families were not closely related. Our study showed that targeted NGS is an effective tool for diagnosis of genetic deafness and that p.G141R in ILDR1 may be a relatively frequent mutation for DFNB42 in Chinese Hans.

Highlights

One in every thousand children suffers congenital or early-onset deafness
In 2011, Borck et al first reported several loss-of-function mutations in ILDR1 resulting in autosomal recessive hearing impairment DFNB42 [3]
For the three affected individuals in both families (F1-II-1, F2-II-1, and F2-II-2), the hearing impairment was prelingual and bilateral, and the severity ranged from moderate (F1-II-1) to profound (F2-II-1 and F2-II-2) (Figure 1(d))

Summary

Introduction

One in every thousand children suffers congenital or early-onset deafness. More than 100 genes and 150 loci have been identified to be associated with nonsyndromic hearing impairment (Hereditary Hearing Loss Homepage) (http://hereditaryhearingloss.org), with approximately 80% of cases being autosomal recessive [2]. Mutations in the ILDR1 gene (OMIM 609739) lead to autosomal recessive nonsyndromic deafness DFNB42. ILDR1 encodes the immunoglobulin-like domain containing receptor 1, a predicted type 1 transmembrane protein. It is widely expressed in a variety of tissues including prostate, testes, pancreas, and kidney. In 2011, Borck et al first reported several loss-of-function mutations in ILDR1 resulting in autosomal recessive hearing impairment DFNB42 [3]. Evidence suggested that IDLR1 functions as a water barrier at the tricellular tight junction [5]

Methods

Results

Conclusion