title: Steroid 21-hydroxylase gene mutational spectrum in 50 Tunisian patients: characterization of three novel polymorphisms.
abstract: Congenital adrenal hyperplasia (CAH) is an autosomal recessive disease of steroid biosynthesis in humans. More than 90% of all CAH cases are caused by mutations of the 21-hydroxylase gene (CYP21A2), and approximately 75% of the defective CYP21A2 genes are generated through an intergenic recombination with the neighboring CYP21A1P pseudogene. In this study, the CYP21A2 gene was genotyped in 50 patients in Tunisia with the clinical diagnosis of 21-hydroxylase deficiency. CYP21A2 mutations were identified in 87% of the alleles. The most common point mutation in our population was the pseudogene specific variant p.Q318X (26%). Three novel single nucleotide polymorphism (SNP) loci were identified in the CYP21A2 gene which seems to be specific for the Tunisian population. The overall concordance between genotype and phenotype was 98%. With this study the molecular basis of CAH has been characterized, providing useful results for clinicians in terms of prediction of disease severity, genetic and prenatal counseling.
authors: Laboratory of Human Cytogenetics, Molecular Genetics and Reproductive Biology, Farhat Hached University Hospital, Street Ibn El Jazzar, 4000 Sousse, Tunisia. ilhem_bc@yahoo.fr
authors: Ilhem
authors: I
authors: Ben Charfeddine
authors: Felix G
authors: FG
authors: Riepe
authors: Eric
authors: E
authors: Clauser
authors: Abdelkarim
authors: A
authors: Ayedi
authors: Saloua
authors: S
authors: Makni
authors: Mohamed Tahar
authors: MT
authors: Sfar
authors: Hassen
authors: H
authors: Sboui
authors: Najoua
authors: N
authors: Kahloul
authors: Hechmi
authors: H
authors: Ben Hamouda
authors: Slaheddine
authors: S
authors: Chouchane
authors: Sihem
authors: S
authors: Trimech
authors: Noura
authors: N
authors: Zouari
authors: Samir
authors: S
authors: M'Rabet
authors: Fathi
authors: F
authors: Amri
authors: Ali
authors: A
authors: Saad
authors: Paul-Martin
authors: PM
authors: Holterhus
authors: Moez
authors: M
authors: Gribaa
mesh_terms: D000293:Adolescent; D000312:Adrenal Hyperplasia, Congenital / Q000208:ethnology / Q000235:genetics; D000328:Adult; D000483:Alleles; D001483:Base Sequence; D002648:Child; D002675:Child, Preschool; D005260:Female; D056726:Genetic Association Studies; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D017354:Point Mutation; D020641:Polymorphism, Single Nucleotide; D011544:Pseudogenes; D013255:Steroid 21-Hydroxylase / Q000235:genetics*; D014416:Tunisia / Q000208:ethnology
chemical_list: C531510:CYP21A2 protein, human; D013255:Steroid 21-Hydroxylase