Resumo

GUTIERREZ GARCIA, Enna; BARRIOS GARCIA, Bárbara  e  ARCAS ERMESO, Gretsy. THE HETEROCYGOTIC STATE FOR MUTATIONS OF THE PHENYLALANINE HYDROXYLASE GENE AS A FETAL RISK FACTOR. Rev Cubana Pediatr [online]. 2005, vol.77, n.1, pp. 0-0. ISSN 1561-3119.

Hyperphenylalaninemias are very heterogenous congenital errors of metabolism, both genetical and clinically. At present, more than 450 mutations are known in the phenylalanine hydroxylase gene and they are defined as the elevation of the phenylalanine levels above 120 µmol/L (2 mg/dL). The offspring of women with hyperphenylalaninemias may be affected due to the elevation of phenylalanine within the uterus by the transplacental gradient in favor of the feto. As part of our research, a study was conducted by the test of tolerance to phenylalanine in 37 mothers of children with unspecific mental retardation. It was found that 5 were heterocygotic and 2 homocygotic for the mutation of phenylalanine hydroxylase gene, which indicates a frequency higher than that of the general population. In our sample, it was observed a relation between the heterocygosis state of hyperphenylalaninemias and fetal damage.

Palavras-chave : Hyperphenylalaninemias; phenylalanine hydroxylase enzime; phenylalanine aminoacid; mutation; gene.