Genetic linkage analysis of DFNB39 locus in families with autosomal recessive non-syndromic hearing loss (ARNSHL) from Khuzestan province

Hearing loss (HL) is a most common sensory deficit in humans and approximately one in 1,000 newborns has severe-to-profound HL. About 50% of HL cases are inherited and approximately 70 percent of HL cases are Non-syndromic that about 80 percent of this type of HL is inherited in recessive manner (ARNSHL). This is a heterogeneous disease and its prevalence is higher in developing countries. In Iran due to high rate of consanguinity has high frequency, too. The purpose of the present study was to investigate genetic linkage analysis of DFNB39 locus in families with autosomal recessive nonsyndromic HL from Khuzestan province.
In this descriptive laboratory study, to determine type and frequency of HGF mutations 300 individuals of 25 families from Khuzestan province with autosomal recessive nonsyndromic hearing loss were examined. Selected families in this study had consanguinity and had at least 2 patients and also they were negative for GJB2 gene mutations. Linkage analysis was performed by 6 markers STR (Short tandem repeats) which were located in or were tightly linked to DFNB39 locus conventional PCR and PAGE.
After examining different families, it was revealed non of the families did not show linkage to the DFNB39 locus. Lack of HGF gene mutations in mentioned family suggests that the HGF's mutations probably have no role in causing HL in the studied families.
Based on the results of this study, DFNB39 locus may not be important role in causing hearing loss of population studied. However, further studies are necessary to determine more precisely the role of this locus in hearing loss in Iranian population.