Variation of site-specific methylation patterns in the factor VIII (F8C) gene in human sperm DNA.

The methylation status of 12 CpG sites in three exons of the human factor VIII (F8C) gene was examined by bisulphite genomic sequencing of human sperm DNA from 14 European Caucasians and Asians. Different CpG sites were found to vary in their methylation status both within and between individuals. Strand differences in methylation status were also detected at certain sites, a finding that could reflect hemi-methylation. No evidence for systematic deviations in methylation status were found between the two ethnic groups. Only a limited correlation was observed between the level of methylation of specific CpG sites in sperm DNA and their mutability, a finding that is probably attributable to the pattern of methylation observed in mature spermatocytes not being representative of that of the germline.