Genotype-phenotype correlation in patients with phenylketonuria

Phenylketonuria (PKU) is an autosomal recessive metabolic disease characterized primarily by motor and mental retardation and microcephaly. In this study, demographic information, diagnostic blood PA levels, median blood PA levels during follow-up period, treatment methods and developmental stages were evaluated retrospectively on 422 patients who were diagnosed with hyperphenylalaninemia and whose genotypes were anlayzed. There was a significant decrease in 1st degree kinship rates of the parents of patients. In the patients who presented in the neonatal period, the incidence of mild HPA was found to be higher than the ones who presented in infancy. Follow-up of our patients FA follow-up in our patients was found to be much better than in Western societies. In terms of maternal PKU, more than half of the female patients were in the risk group. It was observed that the patients who applied in the neonatal period were controlled well and the patients who applied in the infancy period had a higher rate of being in the poor control group. It was determined that half of our patients who were given a restricted diet from phenylalanine failed to control their blood PA levels and all patients, who had BH4 response in the beginning and developed resistance, were in risky or poor control groups. No significant difference was found between the Denver test and median PA levels of patients during follow-up periods. It can be concluded that histroy of diet adaptation of patients with anormal WISC-R test results is very likely to be in poor condition, but it cannot be foreseen that a patient with a normal WISC-R finding had a good or bad diet regimen in the past. It was shown that deletion or nonsense mutations worsened the phenotype and increased the rate of abnormality in WISC-R results, while missense mutations caused milder phenotypes. Significant and specific relationships were found between specific allelles and genotypes when compared with phenotypes, median blood PA levels during follow-up periods and treatment types of patients.