Common and Newly Identified PAH Gene Mutations in Families with Phenylketonuria in the Khuzestan Province

Background: Phenylketonuria (PKU) is an amino acid metabolic disorder that can impact a patient’s life and diet. The main characteristic of the disease is several mutations of the phenylalanine hydroxylase (PAH) enzyme, whose gene mutations have been identified in different societies around the world. Objectives: Considering different mutations in different societies, in the current study, we aimed to determine PAH gene mutations in families involved with PKU in Khuzestan province. Methods: In order to screen the PAH gene mutations in the study population, DNA extraction was performed for all samples. The polymerase chain reaction (PCR) method was conducted using specific primer sequences to investigate the mutation spectra of exons 1 to 11 and exon-intron regions in the PAH gene. Analyzing the PCR product was performed by agarose gel electrophoresis. The PCR product was then used in the sequencing section of the study. Results: Nucleotide sequence evaluation and analysis of the study samples showed two IVS10-11 G > A and G > C IVS2 + 5 mutations located in introns 10 and 2, respectively. The IVS10-11 G > A mutation was one of the common mutations, while the G > C IVS2 + 5 (Accession number LC611730.1) mutation was found to be a new mutation among the study population. The other finding was that both identified mutations were heterozygous in parents and homozygous in children with PKU. Conclusions: In addition to the common PAH gene mutation, the newly found mutation can pave the way toward understanding and establishing a better strategy for managing PKU symptoms in children.