Genetic screening for patients with azoospermia and severe oligo-asthenospermia

In order to explore the genetic defects of patients with azoospermia or sev ere oligoasthenospermia, screening examinations were carried out for the ch romosome disorder and gene deletion of the Y chromosome for 220 male infert ility patients. The present results show that, the total prevalence of gene tic defects is 23.6%, including 38 patients (28.4%) with chromosome disorde r and 14 patients (16.8%) with gene deletion in the Yq arm. The most preval ent chromosome anomaly is 47XXY (Klinefelter's syndrome), which includes 18 cases of pure type and three cases of mosaic type. Variable autosomal tran slocations occurred in both the azoospermia group (5.2%) and the oligo-asth enospermia group (5.8%) with similar prevalence. A total of 22 patients had deletions of the variable, interstitial portion of the Yq arm. These gene deletions are distributed not only inside the AZF region, but also outside of this region. The severity of deletions is not well correlated to the cli nical testicular function of the patients. We conclude that chromosome diso rder and gene deletions are the causative factors of patients with azoosper mia and oligo-asthenospermia. Genetic screening should be a routine examina tion for them before the use of assisted-reproductive technologies.