Assessing the Correlation Between Phospholipase C Zeta Measurements and Semen Parameters

With declining fertility rates Worldwide, Assisted Reproductive Technology is seen as a viable solution for infertility, however, individual success rates following ART remain relatively low, rarely exceeding \~50%. The European Society for Human Reproduction and Embryology (ESHRE) indicates pregnancy rates per embryo transfer remain below 50%. Additionally, male infertility is regarded as a leading contributor to global infertility with approximately a third of cases attributed to genetic causes while half of the cases remain unexplained.

In this observational study we investigate the correlation between phospholipase C Zeta (PLCζ ) measurements and semen parameters. PLCζ is a sperm-specific protein which is introduced into a mature egg (oocyte) following gamete fusion and upon introduction, PLCζ is believed to initiate a series of characteristic calcium ion oscillations which lead to oocyte activation and persist beyond the completion of meiosis.

Mounting evidence implicates defects in PLCζ in cases of male factor infertility where intracytoplasmic sperm injection (ICSI; whereby a single sperm is injected into the oocyte) is unsuccessful. Furthermore, defects in PLCζ are also increasingly implicated in cases of male sub-fertility, which affects a much larger proportion of the global population. Numerous studies now indicate that PLCζ not only holds significant value as a therapeutic to rescue cases of ICSI failure, but also as a prognostic diagnostic test of male fertility. Indeed, the reduction or absence of normal PLCζ within sperm has been linked to cases of male factor infertility in humans, either due to inactivation through mutation, due to abrogation of protein levels in sperm as a result of mutation in the PLCζ promoter, or mutations within coding exonic regions of the PLCζ gene. Such data indicate both therapeutic, and diagnostic applications for PLCζ within the fertility clinic. This study seeks to determine the effect of abnormal PLCζ on semen parameters and correlate that with downstream events including clinical pregnancy and live birth rates.