Cytogenetic and molecular analysis of infertile Chinese men: karyotypic abnormalities, Y-chromosome microdeletions, and CAG and GGN repeat polymorphisms in the androgen receptor gene

Chromosome abnormalities, Y-chromosome microde­letions, and androgen receptor gene CAG and GGN repeat polymor­phisms in infertile Chinese men featuring severe oligospermia and azoospermia were analyzed. Ninety-six fertile men and 189 non-ob­structive infertile men, including 125 patients with azoospermia and 64 with severe oligozoospermia, were studied. Seventeen infertile men (9.0%) carried a chromosome abnormality. Twenty (10.6%) carried a Y-chromosome microdeletion. In the remainder of the patients and con­trols, GGN and CAG repeats were sequenced. Short GGN repeats (n < 23) appeared to be associated with defective spermatogenesis, with the number of GGN repeats strongly correlated with sperm counts. No sig­nificant difference in CAG repeats was found between patients and con­trols, nor were CAG repeats correlated with sperm counts. However, for CAG repeats ranging between 24 and 25, there was a >2.5-fold risk (OR = 2.539, 95%CI = 1.206-5.344, P < 0.05) of severe oligospermia and azoospermia. Our results confirmed the significant role of chromo­some abnormalities, Y-chromosome microdeletions, and GGN repeats in Chinese male infertility.