Array comparative genomic hybridization analysis does not show genetic alterations in spermatozoa and offspring generated after spermatogonial stem cell transplantation in the mouse

Abstract
BACKGROUND The most promising procedure to restore fertility in male childhood cancer patients is spermatogonial stem cell transplantation (SSCT). Although the efficiency of SSCT has been proven in the mouse model, its safety needs to be investigated too before considering any implementation in the clinic. To examine the incidence of genetic abnormalities after SSCT, the karyotypes of donor-derived spermatozoa and offspring were analyzed. METHODS Donor cells were obtained from prepubertal mice and introduced in the seminiferous tubules of genetically sterile W/W(v) mice. Five to 10 months after SSCT, DNA was extracted from epididymal sperm to perform array comparative genomic hybridization (aCGH) analysis. In addition, spermatozoa, liver and kidney from the offspring were subjected to aCGH analysis. RESULTS Numerical chromosomal aberrations could not be detected in spermatozoa from transplanted males, nor in their offspring. The few genetic deviations (deletions, amplifications) observed were all polymorphisms. CONCLUSIONS No major genetic alterations could be detected after SSCT. These data are supportive for further development of SSCT as a strategy for fertility restoration.