Fenilcetonúria Revisitada

Laura Vilarinho*, Ana Queirós*, Paula Leandro†, Isabel Tavares de Almeida†, Isabel Rivera†

 

*Laboratório Nacional de Rastreios, Instituto de Genética Médica, Porto; † Unidade de Biologia Molecular e Biopatologia Experimental, Centro de Patogénese Molecular, Faculdade de Farmácia de Lisboa

 

Resumo

A fenilcetonúria é a aminoacidopatia mais comum da população caucasiana e tornou-se o paradigma de uma doença que pode ser facilmente identificada através de um rastreio sistemático e que, tratada atempadamente, evita a deterioração neurológica grave com atraso mental profundo. Em Portugal, até ao final de 2005, foram rastreados 2.481.988 recém-nascidos e detectados 226 doentes através do Programa Nacional para o Diagnóstico Precoce, sendo a prevalência desta doença no nosso país de 1/11.031 recémnascidos. A fenilcetonúria constitui uma patologia com grande heterogeneidade molecular conforme é demonstrado pelas 29 mutações diferentes identificadas nos 103 doentes caracterizados de 98 famílias, correspondendo a 196 alelos independentes, sendo a IVS10nt-11G→A a mutação mais frequente (17,3%).

Palavras-chave: PKU; fenilcetonúria; rastreio neonatal; programa nacional de diagnóstico precoce.

 

Phenylketonuria Revisited

Abstract

PKU, the most common amino acid disorder in the Caucasian population, became the paradigma of an easily diagnosed disease by neonatal screening. Early treatment prevents neurological damage and severe mental retardation. In Portugal, until the end of 2005, 2,481,988 newborns were screened for by the National Neonatal Screening Program and 226 PKU patients identified, displaying a prevalence of 1/11,031. One-hundred and three patients, corresponding to 196 independent alleles, were fully genotyped. Among the 29 different mutations identified, IVS10nt-11G→A revealed to be the most frequent one (17.3%). These results demonstrate that, as expected, PKU is a highly heterogeneous disease at the molecular level.

Key-words: PKU; phenylketonuria; neonatal screening; newborn screening program.

 

 

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Correspondência:

Dr.ª Laura Vilarinho

Laboratório Nacional de Rastreios

Instituto de Genética Médica Praça Pedro Nunes, 88

4099-028 Porto

e-mail: laura.vilarinho@igm.min-saude.pt