Comprehensive 5-year study of cytogenetic aberrations in 668 infertile men.
OBJECTIVE
The causes of male infertility are heterogeneous but more than 50% of cases have a genetic basis. Specific genetic defects have been identified in less than 20% of infertile males and, thus, most causes remain to be elucidated. The most common cytogenetic defects associated with nonobstructive azoospermia are numerical and structural chromosome abnormalities, including Klinefelter syndrome (47,XXY) and Y chromosome microdeletions. To refine the incidence and nature of chromosomal aberrations in males with infertility we reviewed cytogenetic results in 668 infertile men with oligozoospermia and azoospermia.


METHODS
High resolution Giemsa banding chromosome analysis and/or fluorescence in situ hybridization were done in 668 infertile males referred for routine cytogenetic analysis between January 2004 and March 2009.


RESULTS
The overall incidence of chromosomal abnormalities was about 8.2%. Of the 55 patients with abnormal cytogenetic findings sex chromosome aneuploidies were observed in 29 (53%), including Klinefelter syndrome in 27 (49%). Structural chromosome abnormalities involving autosomes (29%) and sex chromosomes (18%) were detected in 26 infertile men. Abnormal cytogenetic findings were observed in 35 of 264 patients (13.3%) with azoospermia and 19 of 365 (5.2%) with oligozoospermia.


CONCLUSIONS
Structural chromosomal defects and low level sex chromosome mosaicism are common in oligozoospermia cases. Extensive cytogenetic assessment and fluorescence in situ hybridization may improve the detection rate in males with oligozoospermia. These findings highlight the need for efficient genetic testing in infertile men so that couples may make informed decisions on assisted reproductive technologies to achieve parenthood.
Yatsenko
Alexander N
AN
Department of Pathology, Baylor College of Medicine, Houston, Texas 77030, USA.
Yatsenko
Svetlana A
SA
Weedin
John W
JW
Lawrence
Amy E
AE
Patel
Ankita
A
Peacock
Sandra
S
Matzuk
Martin M
MM
Lamb
Dolores J
DJ
Cheung
Sau Wai
SW
Lipshultz
Larry I
LI
D000328:Adult; D053713:Azoospermia / Q000235:genetics*; D002869:Chromosome Aberrations; D006801:Humans; D008297:Male; D008875:Middle Aged; D009845:Oligospermia / Q000235:genetics*; D012189:Retrospective Studies; D013997:Time Factors; D055815:Young Adult