Report of VNTR with 13 repeats linked to phenylalanine hydroxylase locus in unaffected members of two PKUfamilies

Phenylketonuria [PKU] is one of the most common metabolic inborn diseases caused by mutations in the phenylalanine hydroxylase [PAH] gene. This gene is linked to a variable number of tandem repeats [VNTR] region which is a polymorphic marker that facilitates the implementation of prenatal diagnosis and carrier screening. In this study, VNTR with 13 repeats that has not been reported previously was observed in 2 PKU families from Fars province, south of Iran. This allele showed 4% frequency in normal individuals