Delineating the Methylome of Human Oocyte and Sibling Polar Body by Single‐cell Whole Genome Bisulfite sequencing

Abstract

We hypothesized that polar body can reflect transcriptomic and epigenetic landscape of sibling oocyte. Single-cell parallel methylome and transcriptome sequencing (scM&T-seq) is a powerful method that simultaneously reveals the transcriptome and methylome at single-cell and single-base resolution. Here we applied the method to reveal the transcriptomic and epigenetic landscape of oocyte and its sibling polar body. we conducted single-cell RNA (scRNA) sequencing for human oocytes and polar bodies. However, the transcriptome in human polar body cannot reflect that in human oocytes. Therefore, we investigated the methylome of polar body and oocyte. Single-cell Whole Genome Bisulfite Sequencing (scWGBS) demonstrated a good genome coverage in both oocyte and polar body. Here we found that the human polar body has a highly resembled methylome pattern to its sibling oocyte. Our result showed that oocyte and polar body shared the similar methylation level at most of the imprinted genes, such as SNRPN and IGF2R. In conclusion, these findings indicate that human polar body can deduce the human oocyte methylome by scWGBS.