Molecular analysis of most common mutations in Phenylalanine hydroxylase gene in Iranian population

Phenylketonuria (PKU) is the most prevalent disorder of amino acid metabolism. It is one of the most important preventable causes of mental retardation. Incidence of PKU in Iran has been estimated at 1 in 3627 births. The aim of this study is to assess the prevalence of PKU mutations in Iranian population. For this purpose, 150 unrelated patients with classic PKU (300 alleles) were screened for 10 mutations (IVS10-11g>a, R252W, R261X, R261Q, IVS11nt1, R408W, R408Q, L333F, 364delG and S67P) using polymerase chain reaction-restriction fragment length polymorphism. The predominant mutations in this population sample are IVS10-11g>a, R261Q, IVS11nt1g>c and R252W with the frequency 21.7%, 9%, 6.7% and 4.7% respectively. In addition, 6 other mutations have been identified at relatively low frequencies (R261X (4%), 364LdelG (3.7%), L333F (2%), R408W, R408Q and S67P (0.33%)). These informations provide a good basis for direct DNA diagnosis of PKU in this population.