Molecular analyses of Phenylketonuria in the intellectually disabled children from Faisalabad, Punjab, Pakistan

Background: Phenylketonuria (PKU) is a rare inherited metabolic disorder, caused by mutations in the phenylalanine hydroxylase (PAH). It is a treatable disorder if diagnosed earlier in life. The objective was to identify PKU patient(s) in the intellectually disabled children. Methods: Blood samples (n=100) were collected from intellectually disabled children from Faisalabad, Pakistan. Screening was performed on plasma samples through HPLC, and DNA samples were examined for mutational analysis of PAH through direct PCR and SSCP analyses. Results: 85% consanguinity rate, the average BMI (16.15 kg/m2) and head circumference (50.21 cm) was observed. Moreover, through biochemical and genetic analyses, not a single PKU patient was identified. Conclusion: Based on just one previous report and our small dataset it is concluded that either mutations are not common in the hotspot regions or chances of occurrence of PKU might be rare in Pakistan. Moreover, there is a need of more research on large scale to find the incidence of PKU in Pakistan.