title: The biochemical basis for genotyping 21-hydroxylase deficiency.
abstract: We describe three different forms of 21-hydroxylase deficiency-classical congenital adrenal hyperplasia (CAH), late-onset 21-hydroxylase deficiency, and cryptic 21-hydroxylase deficiency-and we present hormonal standards by which to assign the appropriate 21-hydroxylase deficiency genotype for these disorders. The late-onset and cryptic forms of 21-hydroxylase deficiency are biochemically indistinguishable, although patients with the late-onset disorder present with marked clinical symptoms (e.g. virilization) whereas patients with cryptic 21-hydroxylase deficiency are clinically asymptomatic. Our latest studies suggest that late-onset 21-hydroxylase deficiency, like the classical and cryptic 21-hydroxylase deficiencies, is also genetically linked to HLA, the major histocompatibility complex of man. Our biochemical findings provide evidence that a spectrum of 21-hydroxylase deficiencies exist in the population.
mesh_terms: D000293:Adolescent; D000312:Adrenal Hyperplasia, Congenital / Q000145:classification* / Q000175:diagnosis / Q000235:genetics; D000324:Adrenocorticotropic Hormone; D000328:Adult; D002648:Child; D005260:Female; D008040:Genetic Linkage; D005838:Genotype; D006680:HLA Antigens / Q000235:genetics; D006801:Humans; D008297:Male; D013255:Steroid 21-Hydroxylase / Q000235:genetics; D013250:Steroid Hydroxylases / Q000172:deficiency*; D013739:Testosterone / Q000097:blood; D013997:Time Factors
chemical_list: D006680:HLA Antigens; D013739:Testosterone; D000324:Adrenocorticotropic Hormone; D013250:Steroid Hydroxylases; D013255:Steroid 21-Hydroxylase