OBJECTIVETo determine microdeletion loci and the characteristic of Y chromosome azoospermia factor(AZF) associated with Chinese idiopathic azoospermia or severe oligozoospermia and hence to provide a theoretic basis for gene diagnosis of AZF microdeletion in Chinese infertility men.

METHODSThe subjects of this study included 134 cases of azoospermia and 118 severe oligozoospermia, and 210 healthy male controls. With multiplex PCR technique, an analysis of 15 sequence tag sites(STS) in AZFa, AZFb and AZFc microdeletion was performed.

RESULTSNo microdeletion was detected in controls whereas 13 STS loci microdeletions existed in cases, including sY84 and sY86 in AZFa; sY121, sY123, sY124, sY127, sY134 and sy133 in AZFb; sY152, sY242, sY254, sY255 and sY157 in AZFc. Five azoospermia patients were involved in AZFa microdeletions, 7 azoospermia and 3 severe oligozoospermia patients in AZFb, and 14 azoospermia and 18 severe oligozoospermia patients in AZFc. The prevalence rates of microdeletion in AZFa, AZFb and AZFc were 2.0%,4.0% and 12.7% respectively. The microdeletion rate showed statistically significant difference between the cases and controls.

CONCLUSIONThis study revealed an association between the microdeletion of 13 STS loci of AZF region and the idiopathic azoospermia or severe oligozoospermia in Chinese. There is no evidence to identify the genetic polymorphism of the above STS loci. The frequency and distribution characteristic of AZF microdeletion are similar to those of Caucasians. As candidate loci the 13 STS are useful in clinical gene diagnosis for the detection of AZF microdeletion in Chinese idiopathic azoospermia and severe oligozoospermia.