Gene conversion in steroid 21-hydroxylase genes

Am J Hum Genet. 1990 Jun;46(6):1178-86.

Abstract

The steroid 21-hydroxylase gene, CYP21B, encodes cytochrome P450c21, which mediates 21-hydroxylation. The gene is located about 30 kb downstream from pseudogene CYP21A. The CYP21A gene is homologous to the CYP21B gene but contains some mutations, including a C----T change which leads a termination codon, TAG, in the eighth exon. We found the same change in a mutant CYP21B gene isolated from a patient with 21-hydroxylase deficiency. Furthermore, a reciprocal change--i.e., a T----C change in the eighth exon of the CYP21A gene--was observed in the Japanese population and was associated with the two HLA haplotypes, HLA-B44-DRw13 and HLA-Bw46-DRw8. These changes may be considered the result of gene conversion-like events.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adrenal Hyperplasia, Congenital
  • Base Sequence
  • Blotting, Southern
  • Chromosome Mapping
  • Female
  • Gene Conversion*
  • Genes
  • HLA-B Antigens / genetics
  • HLA-B44 Antigen
  • Haplotypes
  • Humans
  • Japan
  • Male
  • Molecular Sequence Data
  • Mutation
  • Polymorphism, Restriction Fragment Length
  • Steroid 21-Hydroxylase / genetics*
  • Steroid Hydroxylases / genetics*

Substances

  • HLA-B Antigens
  • HLA-B44 Antigen
  • Steroid Hydroxylases
  • Steroid 21-Hydroxylase