期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:1992
卷号:89
期号:15
页码:7232-7236
DOI:10.1073/pnas.89.15.7232
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:Lesions in the gene encoding steroid 21-hydroxylase [steroid hydrogen-donor: oxygen oxidoreductase (21-hydroxylating), EC 1.14.99.10 ] result in defective adrenal steroid synthesis; the severe forms are known as congenital adrenal hyperplasia. To facilitate complete characterization of mutations in this region of tandemly repeated genes, we have developed selective PCR amplification and direct sequencing of full-length nonpseudogene steroid 21-hydroxylase genes. This technique identifies known mutations, characterizes or excludes unknown mutations, and determines the gene-copy number. Three additional defective alleles were found. A Gly-292----Ser mutation and a frameshift mutation at Arg-484 (GG----C) were identified in patients with severe steroid 21-hydroxylase deficiency. An allele with three additional sequence variations--C----T at 4 bases upstream of translation initiation, Pro-106----Leu, and Pro-454----Ser--were identified in two siblings with late-onset deficiency. Pro-454 is conserved in four species, indicating its importance for normal enzyme function. Functional consequences of individual alleles have been determined in vivo by studying individuals with only one steroid 21-hydroxylase gene. Detailed analyses of clinical data revealed that genotyping could predict the clinical course of the disease. The locations of disease-causing mutations on different haplotypes of the steroid 21-hydroxylase gene region are described.