Analysis for microdeletions of Y chromosome in a single spermatozoon from a man with severe oligozoospermia

Since the association between Y chromosome deletions and spermatogenic failure was demonstrated in 1976, there have been many reports of Y chromosome microdeletions. Peripheral blood lymphocytes (PBLs) have been used for the analysis because the method is convenient, materials are easy to obtain, and PBL genomic DNA is similar to that of germ cells such as spermatozoa. However, PBLs originate from somatic tissue, not from germ cells. In this study, we analyzed 30 spermatozoa in semen ejaculated by an infertile male with Y chromosome microdeletions, while 50 spermatozoa from a normal fertile male were used as a control. The same Y chromosome microdeletion as that found in PBL was identified in each of the 12 spermatozoa which contained the Y chromosome in the infertile patient. These results indicated that spermatozoa (germ cells) had the same Y chromosome microdeletion as PBL (somatic cells). This supports the conjecture that microdeletions are transmitted to the next generation via the treatment of infertility by intracytoplasmic sperm injection.