Sudden changing of pathogenic genes in patients with phenylketonuria

Abstract

Objective To analyze the types of phenylalanine hydroxylase which are the pathogenic genes in patients with phenylketonuria and provide a science theoretical basis for the disease diagnosis and prenatal diagnosis. Methods 36 patients with phenylketonuria were randomly selected as a test group and 36 unrelated normal members a control group. The phenylalanine hydroxylase genes in both groups were detected using PCR method and were analyzed. Results 13 expressed regions were found with phenylalanine hydroxylase genes in teh test group; and 63 mutant genes had been confirmed and belonged to 21 different types. The total detection rate was 87.5%; among which, R243Q (27.78%) had highest mutant frequency, and followed by EX6-96A>G(11.11%), R413P(5.56%), R111X(4.17%), R261Q(4.17%), Y356X(4.17%), and V399V(4.17%). The mutation sites appeared in the 3rd, 5th, 6th, 7th, 9th, 10th, 11th, and 12th expressed regions; among which, the 7th (40.28%) changed most, and followed by the 6th (13.89%), 11th (11.11%), and 12th (8.33%). What’s more, the test results showed that the 12th expressed gene occurred a D415Y Messene mutation, which was not found in the control group and this result wass also not recorded in International PAH gene mutation database. Conclusions Zhaoqing, Guandong province is a place in which patients with phenylketonuria can be easily found with mutant genes marked R243Q, EX6-96A>G, R413P, R111X, R261Q, Y356X, and V399V. The mutation sites mainly appear in the 3rd, 5th, 6th, 7th, 9th, 10th, 11th, and 12th expressed regions. Besides, a D415Y Messene mutation was found in the 12th gene, which has enriched the PAH gene mutation spectrum. Key words: Phenylketonuria; Phenylalanine hydroxylase; Pathogenic genes; Analysis