Exon Deletion Pattern in Duchene Muscular Dystrophy in North West of Iran

OBJECTIVE Duchene and Becker Muscular Dystrophy (DMD/ BMD) are x-linked disorders that both are the result of heterogeneous mutations in the dystrophin gene. The frequency and distribution of dystrophin gene deletions in DMD/ BMD patients show different patterns among different populations. This study investigates the deletion rate, type, and distribution of this gene in the Azeri Turk population of North West Iran. MATERIALS &METHODS In this study, 110 patients with DMD/ BMD were studied for intragenic deletions in 24 exons and promoter regions of dystrophin genes by using multiplex PCR. RESULTS Deletions were detected in 63 (57.3%) patients, and around 83% localized in the mid-distal hotspot of the gene (on exons 44-52), 21 cases (33.3 %) with single-exon deletions, and 42 cases (66.6%) with multi-exonic deletions. The most frequent deleted exons were exon 50 (15 %) and exon 49 (14%). No deletion was detected in exon 3. CONCLUSION This study suggests that the frequency and pattern of dystrophin gene deletions in DMD/ BMD in the Azeri Turk population of North West Iran occur in the same pattern when compared with other ethnic groups.