Reduced MEK inhibition preserves genomic stability in naive human embryonic stem cells

Nat Methods. 2018 Sep;15(9):732-740. doi: 10.1038/s41592-018-0104-1. Epub 2018 Aug 20.


Human embryonic stem cells (hESCs) can be captured in a primed state in which they resemble the postimplantation epiblast, or in a naive state where they resemble the preimplantation epiblast. Naive-cell-specific culture conditions allow the study of preimplantation development ex vivo but reportedly lead to chromosomal abnormalities, which compromises their utility in research and potential therapeutic applications. Although MEK inhibition is essential for the naive state, here we show that reduced MEK inhibition facilitated the establishment and maintenance of naive hESCs that retained naive-cell-specific features, including global DNA hypomethylation, HERVK expression, and two active X chromosomes. We further show that hESCs cultured under these modified conditions proliferated more rapidly; accrued fewer chromosomal abnormalities; and displayed changes in the phosphorylation levels of MAPK components, regulators of DNA damage/repair, and cell cycle. We thus provide a simple modification to current methods that can enable robust growth and reduced genomic instability in naive hESCs.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • DNA Methylation
  • Embryonic Stem Cells / enzymology
  • Embryonic Stem Cells / metabolism*
  • Genomic Instability*
  • Humans
  • MAP Kinase Kinase Kinases / antagonists & inhibitors*
  • Protein Kinase Inhibitors / pharmacology*
  • Proteome
  • Transcriptome


  • Protein Kinase Inhibitors
  • Proteome
  • MAP Kinase Kinase Kinases