Carrier analysis and prenatal diagnosis of congenital adrenal hyperplasia caused by 21-hydroxylase deficiency in Chinese

Congenital adrenal hyperplasia (CAH) is a common autosomal recessive disord er mainly caused by defects in the steroid 21-hydroxylase (CYP21) gene. We screened 1,000 healthy people, using a previously developed differential PC R method combined with single-strand conformation polymorphism and amplific ation-created restriction site methods for the carrier detection of the CYP 21 gene deficiency. Our results indicated that the rate of occurrence of th e heterozygous CAH carrier was about 12 in 1,000, with a gene frequency of 0.0060 and an incidence frequency of 1 in 28,000 in the Chinese population. In addition, 9 cases of CAH families were performed with prenatal diagnosi s. Among them, 3 cases were diagnosed as the severe form, 4 cases carried t he heterozygous mutation, and 2 were normal. This is the first report of ca rrier frequency analysis and prenatal diagnosis of al-hydroxylase deficienc y in Chinese.