Sex chromosome micromosaicism in infertile men with normal karyotypes.
OBJECTIVE
To define the prevalence of low-level sex chromosome mosaicism in a cohort of infertile men.


METHODS
Prospective cohort study of infertile men.


METHODS
Tertiary university infertility center.


METHODS
One hundred one consecutive men who presented with primary infertility for evaluation.


METHODS
Fluorescent in situ hybridization for X and Y was performed on 200 cells, and if an aberrant sex chromosome complement was noted, 400 cells were counted. For this study, any abnormality in sex chromosome complement was defined as micromosaicism.


METHODS
Low-level sex chromosome mosaicism.


RESULTS
Sixty-seven of these men (67%) had no mosaicism, and 34 men (34%) had micromosaicism. The median percentage of abnormal chromosomes in these men was 2%. The mean age of the men without micromosaicism was lower than for men with micromosaicism (31.1 years vs. 35.2 years). A trend toward higher FSH levels in men with low-level mosaicism was seen. Median sperm density and percent motility were higher in normal men. Percent normal morphology was identical between groups.


CONCLUSIONS
We found low-level sex chromosome mosaicism in 34% of infertile men who presented for evaluation. Men with low-level mosaicism were significantly older. Low-level mosaicism may emerge with advancing age and may therefore help to explain the decline in fertility potential seen in older men.
Schiff
Jonathan D
JD
Department of Urology, Mount Sinai Medical Center, New York, NY 10128, USA. dr.schiff@gmail.com
Luna
Martha
M
Evans
Mark I
MI
Patel
Zamip
Z
Berry
Paula K
PK
Bar-Chama
Natan
N
D000328:Adult; D015331:Cohort Studies; D006801:Humans; D007248:Infertility, Male / Q000453:epidemiology* / Q000235:genetics*; D007621:Karyotyping; D008297:Male; D009030:Mosaicism / Q000706:statistics & numerical data*; D019836:Preimplantation Diagnosis; D015995:Prevalence; D027724:Reproductive Techniques, Assisted; D055101:Semen Analysis / Q000379:methods; D012729:Sex Chromosome Aberrations / Q000706:statistics & numerical data*; D055815:Young Adult