Expression of Retroelements in Mammalian Gametes and Embryos

In Vivo. 2021 Jul-Aug;35(4):1921-1927. doi: 10.21873/invivo.12458.


Retroelements are genetic mobile elements, expressed during male and female gamete differentiation. Retrotransposons are normally regulated by the methylation machinery, chromatin modifications, non-coding RNAs, and transcription factors, while retrotransposition control is of vital importance in cellular proliferation and differentiation process. Retrotransposition requires a transcription step, by a cellular RNA polymerase, followed by reverse transcription of an RNA intermediate to cDNA and its integration into a new genomic locus. Long interspersed elements (LINEs), human endogenous retroviruses (HERVs), short interspersed elements (SINEs) and SINE-VNTR-Alu elements (SVAs) constitute about half of the human genome, play a crucial role in genome organization, structure and function and interfere with several biological procedures. In this mini review, we discuss recent data regarding retroelement expression (LINE-1, HERVK-10, SVA and VL30) and retrotransposition events in mammalian oocytes and spermatozoa, as well as the importance of their impact on human and mouse preimplantation embryo development.

Keywords: Retroelements; embryogenesis; gametogenesis; retrotransposons; review.

Publication types

  • Review

MeSH terms

  • Alu Elements
  • Animals
  • Female
  • Humans
  • Long Interspersed Nucleotide Elements* / genetics
  • Male
  • Mice
  • Oocytes
  • Retroelements* / genetics
  • Short Interspersed Nucleotide Elements


  • Retroelements