对３０例先天性肾上腺皮质增生症患儿的２１－羟化酶基因，应用聚合酶链反应结合等位基因特异性寡核苷酸探针杂交技术，进行了分析。结果表明：有１８例患儿存在各种类型的基因缺陷，与临床类型之间有较明显的相关性。提示２１－羟化酶缺陷的临床不同类型的表现，与在分子水平的基因突变类型有密切关联。 The 21-hydroxylase gene in 30 cases of congenital adrenal hyperplasia was analyzed by polymerase chain reaction combined with allele-specific oligonucleotide probe hybridization. The results showed that: there are 18 cases of children with various types of genetic defects, and clinical manifestations of a more significant correlation between. It suggests that the different clinical manifestations of 21-hydroxylase deficiency are closely related to the types of gene mutations at the molecular level.