Polar Bodies in Assisted Reproductive Technology: Current Progress and Future Perspectives.

Wei Y, Zhang T, Wang YP, Schatten H, Sun QY.

Abstract

During meiotic cell cycle progression, unequal divisions take place resulting in a large oocyte and two diminutive polar bodies. The first polar body contains a subset of bivalent chromosomes, whereas the second polar body contains a haploid set of chromatids. One unique feature of the female gamete is that the polar bodies can provide beneficial information about the genetic background of the oocyte without potentially destroying it. Therefore, polar body biopsies have been applied in preimplantation genetic diagnosis to detect chromosomal or genetic abnormalities that might be inherited to the offspring. Besides the traditional use in preimplantation diagnosis, recent emerging findings suggest that there are additional important roles for polar bodies in assisted reproductive technology. In this paper, we review the new roles of polar bodies in assisted reproductive technology, mainly focusing on single-cell sequencing of the polar body genome to deducing the genomic information of its sibling oocyte, and polar body transfer to prevent the transmission of mtDNA-associated diseases. We also discuss additional potential roles for polar bodies and related key questions in human reproductive health. We believe that further exploration of new roles for polar bodies will contribute to a better understanding of reproductive health, and that polar body manipulation and diagnosis will allow production of more healthy babies.