Genotype-phenotype correlations and BH₄ estimated responsiveness in patients with phenylketonuria from Rio de Janeiro, Southeast Brazil.

ABSTRACT:

Background

Genetic heterogeneity and compound heterozygosis give rise to a continuous spectrum of phenylalanine hydroxylase deficiency and metabolic phenotypes in phenylketonuria (PKU). The most used parameters for evaluating phenotype in PKU are pretreatment phenylalanine (Phe) levels, tolerance for dietary Phe, and Phe overloading test. Phenotype can vary from a "classic" (severe) form to mild hyperphenylalaninemia, which does not require dietary treatment. A subset of patients is responsive to treatment by the cofactor tetrahydrobiopterin (BH₄ ). Genotypes of PKU patients from Rio de Janeiro, Brazil, were compared to predicted and observed phenotypes. Genotype-based estimations of responsiveness to BH₄ were also conducted.

Methods

Phenotype was defin

SUBMITTER: Vieira Neto E 

PROVIDER: S-EPMC6503030 | biostudies-literature | 2019 May

REPOSITORIES: biostudies-literature