Author/Editor     Dolžan, V; Stopar-Obreza, M; Žerjav-Tanšek, M; Breskvar, K; Kržišnik, C; Battelino, T
Title     Mutational spectrum of congenital adrenal hyperplasia in Slovenian patients: a novel Ala15Thr mutation and Pro30Leu within a larger gene conversion associated with a severe form of the disease
Type     članek
Source     Eur J Endocrinol
Vol. and No.     Letnik 149
Publication year     2003
Volume     str. 137-44
ISSN     0804-4643
Language     eng
Abstract     Objective: To analyse the mutational spectrum, the associated haplotypes and the genotype-phenotype correlation, and to design a reliable and rational approach for CYP21 mutation detection in Slovenian congenital adrenal hyperplasia (CAH) patients. Design: Molecular analysis of the CYP21 gene was performed in 36 CAH patients and 79 family members. Methods: Southern blotting, sequence-specific PCR amplification (PCR-SSP), sequence-specific oligonucleotide hybridisation (PCR-SSO) and sequencing were used to detect CYP21 gene deletions, conversions and point mutations. Results: CYP21 gene deletion was the most frequent mutation (36.4%). Large gene conversions detectable only by Southern blotting represented 12.1%, and gene conversions involving the promoter region represented 7.6% of the mutated alleles. The most frequent point mutations were: intron 2 splice mutation 16.7%, I1e172Asn mutation 7.6%, G1n318Stop 7.5% and Pro30Leu 12.2% of alleles. A correlation between the genotype and the clinical phenotype similar to those described for large populations was observed. The finding of Pro30Leu mutation linked to a gene conversion could explain the simple virilising (SV) phenotype in compound heterozygotes for the Pro30Leu and a severe mutation. In two siblings with a salt wasting form of CAH (SW-CAH), a novel mutation AIa15Thr was found on the allele characterised by Pro30Leu mutation and gene conversion involving the promoter region. Conclusions: Our genotyping approach allowed reliable diagnosis of CAH in the Slovenian population. The high frequency of CYP21 gene aberrations on Pro30Leu positive alleles justified systematic searching for a gene conversion in the promoter region using the PCR-SSP reaction.
Descriptors     ADRENAL HYPERPLASIA, CONGENITAL
CHILD
AGE FACTORS
SEX FACTORS
ALLELES
BLOTTING, SOUTHERN
DNA MUTATIONAL ANALYSIS
GENE CONVERSION
GENE DELETION
GENOTYPE
HAPLOTYPES
OLIGONUCLEOTIDES
PHENOTYPE
POINT MUTATION
POLYMERASE CHAIN REACTION
SLOVENIA
STEROID HYDROXYLASES