Screening of three Mediterranean phenylketonuria mutations in Tunisian families

Abstract

Phenylketonuria (PKU; OMIM 261600) is an autosomal recessive disease caused by the liver phenylalanine hydroxylase (PAH) enzyme (EC1.14.16.1) deficiency. If untreated, causes mental retardation. The incidence in Caucasian population is approximately 1:10,000 (Scriver and Kaufman 2001). In Tunisia, it seems to be more frequent with a prevalence of 1 in 7631 (Khemir et al. 2011). To this date, more than 530 mutations in the PAH gene (12q22-q24) have been described (http://www. pahdb.mcgill.ca). The characterization of PKU mutations has been made in many countries, all over the world; nevertheless, to date few studies have been reported on the North African populations. In Mediterranean countries, several mutations have been reported. The most common: IVS10–11G>A seems to be widespread. The G352Vfs delG was reported in Algerian, Italian, French Canadian, Croatian and Lebanese populations (Lyonnet et al. 1989); in Morocco, it was described as the most frequent mutation (Dahri et al. 2010). The E280K mutation was also reported in Mediterranean populations (Guldberg et al. 1993). Since Tunisia is a Mediterranean country, patients with PKU are presumed to have these mutations. The aim of this study was to assess prevalence of the three above mutations among PKU patients collected from paediatric departments of hospitals in Tunis.