Genetic variation of D9S1837 Marker located at TMC1 gene in Iranian population

TMC1 gene mutations are one of the most common causes of autosomal recessive Non-syndromic hearing loss (ARNSHL) in different populations. In view of large size of the gene and the large number of identified mutations in TMC1, use of polymorphic markers is suggested for carrier detection and prenatal diagnosis. The aim of this study was to evaluate informativeness of D9S1837 CA repeat STR marker in five different ethnic of Iranian population. In this descriptive analytical study the locus of D9S1837 within TMC1 gene was genotyped by polymerase chain reaction (PCR), polyacrylamide gel electrophoresis (PAGE) and fluorescent capillary electrophoresis, respectively. Allelic frequency, heterozygosity rate and genotyping data from 165 unrelated healthy individuals were estimated by Gene Marker HID Human STR Identity software, Gene Pop program and Microsatellite Tools software. The result obtained through Gene Pop program indicated the presence of 11 alleles of D9S1837 marker in the Iranian population. The most frequent allele was computed for 239 bp with 36% frequency. Heterozygosity of all investigated ethnic groups was above 70%, but among all Arab and Azeri ethnic groups had the highest heterozygosity (84.8%). The data of PIC value demonstrated that the D9S1837 marker was found highly informative in the examined population. According to the results of this study, D9S1837 marker could be used as an informative tool for carrier detection and prenatal diagnosis of TMC1 based ARNSHL by linkage analysis in Iranian population.