3.3 Analysis of PAH gene mutations in 84 PKU patients
There were 51 kinds of 159 mutated PAH gene alleles in 84 PKU children, consisting of 100 missense mutations, 28 shear mutations, 24 nonsense mutations, and 7 deletion mutations. The mutation detection rate was 94.64% (159/168). The mutation frequency was highest in exon 7, 32.08% (51/159), followed by exons 3 and 12, 13.84% (22/159) and 11.95% (19/159), respectively. Among them, p.r243q was the most commonly observed mutation, accounting for 20.13% (32/159) of all mutations, followed by p.r111x (8.18%), ivs4-1g>A (6.92%), ex6-96a>G (6.29%), and p.r413p (5.66%), while the other mutations were sporadic (Table 2 ).
Table 2 PAH gene mutations in children with PKU in Shaanxi province, China
PAH, phenylalanine hydroxylase; PKU, phenylketonuria