Genetics of congenital adrenal hyperplasia and genotype-phenotype correlation
The mechanisms leading to CYP21A2 gene defects are gene conversion and deletions. The well-established correlation between CYP21A2 mutations and the associated clinical phenotype remains subject to some discordances.
Volume 111, Issue 1, Pages 24–29
Mithra L. Narasimhan, M.B.B.S., Ahmed Khattab, M.D.
Congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency is caused by mutations in the CYP21A2 gene, located on the short arm of chromosome 6. The two main underlying mechanisms of CYP21A2 defects are large gene deletion and conversion. Anticipation of the phenotypes associated with different combinations of CYP21A2 mutations remains the most important determinant in prenatal diagnosis and counseling of the expectant couple who are determined to be at risk for congenital adrenal hyperplasia.