[The mutation spectrum of phenylalanine hydroxylase gene in patients with phenylketonuria in Henan province].

Objective: To investigate the characteristics of the phenylalanine hydroxylase (PAH) gene mutations in patients with phenylketonuria (PKU) in Henan province, China, in order for providing basic information for clinical genetic counseling and prenatal diagnosis.

Methods: All the exons and partial flanking introns of the PAH gene were detected by polymerase chain reaction (PCR) and bi-directional sequencing in 34 patients with PKU from Henan province.

Results: A total of 23 different disease-causing mutations were identified which corresponded to 92.