Population Data on D۷S۲۴۲۵ Marker in Five Ethnic Groups of the Iranian Population: A Highly Informative Marker for Molecular Diagnosis of ARNSHL

Background & Aims: SLC۲۶A۴ gene mutations are the second identifiable genetic cause of autosomal recessive nonsyndromic hearing loss (ARNSHL) after GJB۲ mutations and are currently investigated in molecular diagnosis.In databases, several potential STR markers related to this region have been introduced. In this investigation, the characteristics and informativeness of D۷S۲۴۲۵ CA repeat STR marker in SLC۲۶A۴ gene region was examined in five ethnic groups of the Iranian population. Methods: The locus was genotyped in ۱۶۵ individuals of five different ethnic groups including Fars, Azari, Turkmen, Gilaki, and Arab using polymerase chain reaction (PCR) followed by polyacrylamide gel electrophoresis (PAGE) and fluorescent capillary electrophoresis. In this study, the results were analyzed by GeneMarker HID, Human STR Identity software, GenePop program, and Microsatellite Tools. Results: Analysis of the allelic frequency revealed the presence of ۸ alleles for D۷S۲۴۲۵ marker in the Iranian population, of which the ۲۴۶bp allele at the D۷S۲۴۲۵ locus with ۰.۳۰% frequency was the most frequent. The ۹۳.۹% observed heterozygosity of the Gilak ethnic group was the highest among all ethnic groups. Analysis of deviations of the Hardy-Weinberg equilibrium demonstrated that all the ethnic groups were in equilibrium (P > ۰.۰۵) for D۷S۲۴۲۵ locus. Finally, analysis of PIC value revealed that the D۷S۲۴۲۵ marker could be considered as a highly informative marker in each ethnic group of the Iranian population (PIC value above ۰.۷). Conclusion: Our data suggested that D۷S۲۴۲۵ could be introduced as a highly informative marker in molecular diagnosis of SLC۲۶A۴ based ARNSHL by Linkage analysis