Mutations Analysis of exon 10 - 11 of phenylalanine Hydroxylase gene in phenylketonuria patients from Golestan province

Phenylketonuria (PKU), the most common inborn error of aminoacid metabolism, is an autosomal recessive disorder caused by more than 600 mutations in Phenylalanine Hydroxylase gene (PAH). Distribution pattern of mutations in the PAH gene are specific to each population. The aim of this study was to identify mutations in exons 10 and 11 of the PAH gene in patients with PKU from Golestan Province and compare it with the studies in other parts of Iran. This study is a cross-sectional descriptive study. During a one-year period, twenty- six unrelated PKU patients were identified from different regions of Golestan province. Genomic DNA was extracted from leukocytes using High Pure- Template PCR kit (Roche) and polymerase chain reaction – sequencing method was applied to detect mutations. The identified mutations in this study are: IVS10-11G>A (19.23%) and IVS11+1G>C (7.7%). These patients had classic PKU phenotype. The high frequency of IVS10-11G>A mutation in Golestan province may be related to genetic drift, founder effect, and consanguinity. Moreover investigation of mutations in PAH gene can be a useful tool for molecular detection of PKU disease and carrier detection in this population.