Sperm histone modifications may predict success in human assisted reproduction: a pilot study.

PURPOSE: Currently, assisted reproduction clinics employ various sperm selection techniques to identify the best sperm for fertilization. However, these techniques may not assess crucial sperm traits that can substantially impact embryonic quality. To address this, we propose analyzing diverse histone modifications as potential markers of sperm functionality and success in assisted reproduction techniques. METHODS: Cross-sectional pilot study including infertile male patients attending an infertility clinic in CABA, Argentina between April and August 2019 was performed. We used immunofluorescence techniques to evaluate post-translational modifications of histones in sperm and established correlations with in vitro fertilization outcome and embryo quality. RESULTS: Our findings indicate a negative correlation between H3K4me3 and H3K4me2 marks and fertilization rate and showed a positive correlation of this parameter with H3K9me mark. In addition, there was a positive correlation between H3K27me3 and good embryo quality. CONCLUSIONS: This pilot study proposes a non-invasive strategy to predict embryo quality by analyzing spermatozoa prior to fertilization. The assessment of histone post-translational modifications in sperm samples could provide useful information for the recognition of epigenetic marks that could predict the health of the embryo of an assisted fertilization treatment.