Hurler disease (mucopolysaccharidosis type IH): clinical features and consanguinity in Tunisian population

consanguinity rates have been determined among 14 families with mucopolysaccharidosis type I, seen in the pediatric departments of different geographic areas of Tunisia (Central and Southern areas) for the period August 2004 - August 2011 in order to investigate the relation between consanguinity and this disorder.Clinical and molecular analyses confirmed the diagnosis for MPS type I in the studied families.Most of the Tunisian MPS I patients have been identified at the homozygous status: p.P533R mutation (7 homozygous and one double heterozygous p.L578Q/p.P533R patients; 41.66% of all the investigated MPSI patients), p.F177S (1 homozygous patient; 5.55%), p.L530fs (1 patient; 5.55%), p.Y581X (2 patients; 11.11%), p.F602X (3 patients; 16.66%), p.R628X (1 patient; 5.55%). Another mutation: p.L578Q has been identified at the heterozygous status in the only double heterozygous p.L578Q/p.P533R case. Part of the mutations was the result of a founder effect. These described points are the consequences of the high rate of consanguinity.The high frequency of p.P533R mutation could be explained by the high degree of inbreeding. This is due to the richness of the genetic background of the studied population.A multidisciplinary approach is essential to develop adequate preventive program adapted to the social, cultural, and economic context.The virtual slides for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1863141266606652 webciteMucopolysaccharidoses (MPS) are a group of lysosomal storage and inherited disorders caused by the deficiency of specific enzymes which leads to the lysosomal accumulation of glycosaminoglycanes. Mucopolysaccharidosis type I is caused by a deficiency of the glycosidase alpha-L-iduronidase (α-L-iduronidase iduronohydrolase, EC 3.2.1.76; IDUA) and the resulting accumulation of undergraded dermatan sulfate and heparan sulfate [1]. Accumulation of partially degraded of this macromolecules leads to typical symptoms of lyso