Genetic linkage analysis of the DFNB35 and DFNB42 loci in families with autosomal recessive non-syndromic hearing loss from Khuzestan province

Hearing loss is a common sensorial disorder. There are approximately 360 million affected people all over the world. More than 50% of hearing loss is because of genetics factors. About 70% of inherited hearing loss is due to non-syndromic hearing impairment that Autosomal- recessive inheritance is responsible for about 80% of cases. Autosomal recessive non syndromic hearing loss is very heterogeneous and more than 50 genes have been identified for it. The aimof this study was to investigate the role of DFNB42 (ILDR1) and DFNB35 (ESRRB) mutations in 25 families with ARNSHL from Khuzestan Iran.
This descriptive study was based on linkage analysis and selected 6 STR markers for each locus. This study was performed for 300 individuals from 25 families that had at least two affected, also they had consanguineous marriage. In this study, it was investigated mutations of GJB2 and 3 families with positive result for mutation in GJB2, were excluded from our study.
With linkage analysis, none of selected families was linked to DFNB35 or DFNB42 loci. This study showed that the ILDR1 and ESRRB mutations have no role in hearing loss in studied families.
This study shows that mutations in ILDR1 and ESRRB genes have no important role in incidence of hearing loss in Khuzestan province. This result suggests that studying of other loci that are involved in deafness, can be helpful to identify genetic causes in this disease in the studied population.