Evaluation of the role of mitotic instability in karyotypically normal menwith oligozoospermia

Objective: To estimate the incidence of sex chromosome aneuploidies in the somatic cells of karyotypically normal infertile men and fertile donors. Design: A prospective, two-phase, controlled study. Setting: Reproductive medicine and medical genetics units of a teaching hos pital. Patient(s): Ten patients with oligozoospermia and 10 sperm donors with prov ed fertility, all with a normal karyotype 46 XY. Intervention(s): Multicolor fluorescence in situ hybridization (FISH) of pe ripheral blood lymphocytes using a probe cocktail containing the alpha sate llites DXZ1 for the X centromere and DYZ1 for the heterochromatic region of the long arm of the Y and the radiolabeled alpha satellite D18Z1 for chrom osome is. Main Outcome Measure(s): The incidence of sex chromosome aneuploidies in bo th groups. Result(s): A 13-fold increase in sex chromosome aneuploidies was observed i n the somatic cells of infertile men with "unexplained" oligozoospermia com pared to donors (P=.008). Conclusion(s): These findings provide suggestive evidence for the existence of an inherent mitotic instability in men with unexplained obligozoospermi a. (Fertil Steril(R) 2000;73:51-5. (C) 1999 by American Society for Reprodu ctive Medicine.)