Genetic Analysis of MECP2 Gene in Iranian Patients with Rett Syndrome

Rett syndrome is an X linked dominant neurodevelopmental disorder which almost exclusively affects females. The syndrome is usually caused by mutations in MECP2 gene, which is a nuclear protein that selectively binds CpG dinucleotides in the genome.

To provide further insights into the distribution of mutations in MECP2 gene, we investigated 24 females with clinical characters of Rett syndrome referred to Alzahra University Hospital in Isfahan, Iran during 2015-2017. We sequenced the entire MECP2 coding region and splice sites for detection of point mutations in this gene. Freely available programs including JALVIEW, SIFT, and PolyPhen were used to find out the damaging effects of unknown mutations.

Direct sequencing revealed MECP2 mutations in 13 of the 24 patients. We identified in 13 patients, 10 different mutations in MECP2 gene. Three of these mutations have not been reported elsewhere and are most likely pathogenic.

Defects in MECP2 gene play an important role in pathogenesis of Rett syndrome. Mutations in MECP2 gene can be found in the majority of Iranian RTT patients. We failed to identify mutations in MECP2 gene in 46% of our patients. For these patients, further molecular analysis might be necessary.