Congenital adrenal hyperplasia, also known as CAH, is an inherited disorder affecting
the hormones produced and released by the adrenal glands. Approximately 1 in 12,000 infants is affected by CAH.
The most common type of CAH is called 21-hydroxylase deficiency which is due to
changes in the gene (DNA) that codes for the protein, 21-hydroxylase (CYP21A2).