The Frequency of DYT1 (GAG Deletion) Mutation in Primary Dystonia Patients from Iran

OBJECTIVE: To determine the frequency of DYT1 mutation in Iranian patients affected with primary dystonia. MATERIALS AND METHODS: In this study, we investigated 60 patients with primary dystonia who referred to the Tehran Medical Genetics Laboratory (TMGL) to determine the deletional mutation of 904-906 del GAG in the DYT1 gene. DNA extracted from patients’ peripheral blood was subjected to PCR-sequencing for exon 5 of the DYT1 gene. The collection of samples was based on random sampling. RESULTS: The deletional mutation of 904-906 del GAG in the DYT1 gene (15099 to 15101 based on reference sequence: NG_008049.1) was identified in 11 patients (18.33%). The average age of affected patients with this mutation was 13.64 ± 7.4 years. CONCLUSION: It can be concluded that the DYT1 deletional mutation of 904-906 del GAG has a high frequency in Iranian patients in comparison with other non-Jewish populations. Therefore, this particular mutation may be the main representative of pathogenic DYT1 gene for a large proportion of Iranian patients with primary dystonia.