Differential effects of human papillomavirus DNA types on p53 tumor-suppressor gene apoptosis in sperm.

OBJECTIVE Sperm DNA undergoes apoptotic fragmentation when exposed to HPV DNA. Details of the specific gene regions targeted by HPV in sperm are lacking. The objective of this study was to determine the integrity of exons 5 and 8 of the p53 gene in sperm exposed to HPV DNA. METHODS Washed sperm were exposed to either HLA-DQA1 (control) or HPV type 6b/11, 16, 18, 31, or 33 DNA fragments for 24 h at 37 degrees C. The integrity of sperm p53 exons 5 and 8 was assessed using a novel DNA disc chip assay based on comparative genomic hybridization. RESULTS Fragmentation of exon 5 occurred after exposure to HPV DNA type 18. In contrast, only exon 8 was affected by HPV type 16. HPV DNA from type 31 or 33 was without effect on the p53 exons. Sperm motility but not hyperactivation was reduced in all HPV groups. CONCLUSION The data suggest that different HPV types preferentially degrade different exons of important genes. Decreased motility but not hyperactivation in HPV-exposed sperm suggests retention of some fertilizing capacity and the possibility of transmitting virus-destabilized genes through fertilization.