Pseudogene/functional gene ratio in late-onset 21-hydroxylase-deficient adrenal hyperplasia.
Late-onset adrenal hyperplasia caused by 21-hydroxylase deficiency leads to hyperandrogenic symptoms in 1% to 6% of hyperandrogenic women. Normally there are two 21-hydroxylase genes present in a 1:1 ratio. Gene CYP21A is a nonfunctional pseudogene, whereas CYP21B is an active gene. Abnormalities of the CYP21A/CYP21B gene ratio may serve as a marker for late-onset adrenal hyperplasia. Eight hyperandrogenic patients with late-onset adrenal hyperplasia and five control subjects were studied by evaluation of autoradiograms of Taq I and Kpn I digests by means of laser densitometry. Seven of eight (87%) patients with late-onset adrenal hyperplasia had an abnormal CYP21A/CYP21B gene ratio on laser densitometry, suggestive of CYP21A gene duplication, CYP21B gene deletion, or the conversion of a CYP21B gene to a CYP21A gene. One of the five control subjects had a heterozygous deletion of the CYP21A gene. The CYP21A/CYP21B gene ratio may serve as a useful genetic marker for late-onset adrenal hyperplasia in a non-high-risk population.
Azziz
R
R
Departments of Obstetrics and Gynecology, University of Alabama, Birmingham.
Wells
G
G
Acton
R T
RT
Zacur
H A
HA
D000311:Adrenal Glands / Q000473:pathology*; D000312:Adrenal Hyperplasia, Congenital; D001345:Autoradiography; D004247:DNA; D003720:Densitometry / Q000379:methods; D005260:Female; D005796:Genes; D005819:Genetic Markers; D006680:HLA Antigens / Q000032:analysis / Q000145:classification; D006801:Humans; D007834:Lasers; D009693:Nucleic Acid Hybridization; D011544:Pseudogenes; D013250:Steroid Hydroxylases / Q000172:deficiency*
D005819:Genetic Markers; D006680:HLA Antigens; D004247:DNA; D013250:Steroid Hydroxylases