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

To determine the frequency of DYT1 mutation in Iranian patients affected with primary dystonia.

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.

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.

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.