The Investigation of Haplotype Phasing Efficiency at the PAH Gene Region in Iranian Family Trios

The haplotype phasing is more useful than genotyping markers independently at carrier detection and prenataldiagnosis of diseases. the pah gene region contains several markers used in detection of pku disease. in the presentstudy, the efficiency of bglii-ecori-vntr haplotype phasing in iranian family trios was investigated. then, this informationwas compared with those obtained for unrelated individuals.methods: blood samples were collected from 20 healthy family trios and 60 unrelated individuals. the genomic dna wasextracted by use of salting-out procedure. the two markers bglii and ecori were genotyped by use of pcr-rflp. the genotype ofvntr marker was identified by use of pcr and electrophoresis. the genotyping data obtained from family trios was usedto infer haplotype phase. we also compared this data with results obtained from a widely used method for haplotype frequencyinference from unrelated individuals, the phase program.results: the haplotype phase of all members was only ascertained at eight family trios. the comparison of this data withthe results obtained by use of phase program showed that eight haplotypes [211, 221, 215, 216, 214, 121, 225 and 111] wereinformative haplotypes in iranian population.conclusion: since diversity of bglii-ecori-vntr haplotypes was high in iranian population, haplotype phasing at familytrios was difficult. the results of this study showed that the genotyping data obtained from family trios could not provideenough information for bglii-ecori-vntr haplotype phasing at iranian pku families and the genotyping of other familymembers was necessary at most cases.