Associations Between Eppin Gene Polymorphysms And Sperm Quality Traits In The Chinese Holstein Bulls

Novel single nucleotide polymorphisms (SNP) of the EPPIN gene were investigated in434Chinese bulls by PCR-RFLP and DNA sequencing methods in the present study. The relationships between polymorphisms and haplotype of the EPPIN gene and the sperm quality traits were analyzed in Chinese Holstein bulls for the purpose of selecting molecular maker information to improve the breeding efficiency of high sperm quality.The epididymal protease inhibitor (EPPIN) abounds in human semen and on the surface of human spermatozoa, specifically produced by the testis and epididymis. They play a role beyond innate immunity participating in events related to male fertility, regulation of epididymal function and sperm maturation. Recombinant EPPIN has affected infertility in the immunized monkey and promises to be an effective vaccine for human immuno-contraception.In the present study we detected2single-nucleotide polymorphisms of EPPIN gene in Chinese Holstein bulls, and they were rs43072843(G/A) and g.2119(T/C). rs43072843(G/A) and g.2119(T/C) mutations could be genotyped into three genotypes with PCR-RFLP method by using TaqI and StyI.The results showed that at locus rs43072843(G/A), the bulls’ frozen semen motility with genotype GA was very significantly higher than those with genotype AA(P<0.05); at locus2119(T/C), the bulls’sperm density with genotype CT was significantly higher than those with genotype TT(P<0.05). The two SNPs had no significantly relationship with ejaculate volume, initial sperm motility and frozen semen motility. Four haplotype and9haplotype combinations were found in434Chinese Holstein bulls. The bulls’ initial sperm motility, frozen semen motility and ejaculate volume with genotype combinations GG/CC was the highest in all nine genotype combinations. It may be regard as a choice of molecular maker of bulls with high sperm quality in the future.