Phenylketonuria from Genetics to Clinics: An Iranian Prospect

Phenylketonuria (PKU) is the most common autosomal recessive disorder of amino acid metabolism. Thedisease is caused mainly by mutations in the phenylalanine hydroxylase (PAH) gene, encoding phenylalaninehydroxylase (PAH) enzyme. The PAH enzyme deficiency results in the elevation of phenylalanine inthe blood, which may cause severe irreversible mental retardation in the affected individuals. More than 500different disease causing mutations have been identified in the PAH gene. Direct and indirect molecularapproaches have been developed for carrier detection and prenatal diagnosis of PKU disease. Populationdistribution of the PAH gene mutations and the PKU disease varies in different countries. In view of relativelyhigh prevalence of the disease in Iranian population, investigations toward the elucidation of molecularaspects of the disease were required. In the present article, clinical and molecular basis of the PKU disease,with emphasis on the studies performed in Iranian population, were reviewed.