Adequate male development and spermatogenesis involve a complex sequence of events determined by numerous genes located on various chromosomes. Defects in any step of gene function (or gene product) may lead to failure of testicular development or spermatogenic deficiency.

Male infertility has numerous causes. Some are clearly genetic, some have no known genetic component. Specific genes on the Y chromosome are necessary for normal male development. Defects in meiosis may cause anomalies in chromosomal constitution in progeny, spermatogenic failure, spermatogenic arrest etc. All of those defects have profound effects on male fertility.

We present chromosomal findings in males who were treated for their infertility. The frequency of certain numerical and structural abnormalities is significantly higher in these patients. The influence of specific anomalies on spermatogenic process and fertility is discussed.