Microdeletion of the DAZ (deleted in azoospermia) gene or the YRRM (Y chromosome ribonucleic acid recognition motif) gene does not occur in patients with Klinefelter's syndrome with and without spermatogenesis.

OBJECTIVE: To evaluate the occurrence of microdeletions of the Y chromosome involving the DAZ and YRRM genes in patients with Klinefelter's syndrome with and without spermatogenesis.
DESIGN: Controlled clinical study.
SETTING: Yamagata University Hospital, Yamagata, Japan. PATIENT(S): Patients with Klinefelter's syndrome with spermatogenesis (n = 1) and without spermatogenesis (n = 20) and a control group of men of proven fertility (n = 10). INTERVENTION(S): Blood and semen sampling and testicular biopsy. MAIN OUTCOME MEASURE(S): Semen analysis, polymerase chain reaction amplification of 32 DNA loci on the long arm of the Y chromosome involving the DAZ (deleted in azoospermia) and YRRM (Y chromosome ribonucleic acid recognition motif) genes, and measurement of plasma FSH, LH, and testosterone levels. RESULT(S): No microdeletions of 32 loci were found in any of the patients with Klinefelter's syndrome, either with or without spermatogenesis. Plasma LH and FSH levels were abnormally high and testosterone levels were reduced in all the patients with Klinefelter's syndrome. American Society for Reproductive Medicine.) CONCLUSION(S): Severe impairment of spermatogenesis in patients with Klinefelter's syndrome is not caused by microdeletions of the Y chromosome involving the DAZ and YRRM genes.