[Common mutations of congenital adrenal hyperplasia are also the hotspots for new mutations]

To discuss the genetic diagnosis of congenital adrenal hyperplasia (CAH) and investigate the resource of gene mutations in CAH.

Enzymatic methods with restriction endonucleases that specifically recognized the mutation sites were used to detect the gene mutations in patients with CAH and their relatives. Polymerase chain reaction and direct sequencing were used to identify the mutations in 21-hydroxylase gene, and short tandem repeat (STR) typing was used to determine the sources of the mutations.

One CAH patient had two known mutations in 21-hydroxylase gene, namely the I2g and I172N mutations. The former mutation was inherited from the biological mother and the latter was not inherited.

The 9 common mutations of CAH are also the hotspots for new mutations.