Extended Data Figure 8. Chromosomal aberrations that occur in 2i/L cultured ESCs are in part due to Mek1/2 inhibition.

(a) Quantification of relative RNA and protein levels of pluripotency-related genes between male ESCs in S/L (n=2 technical replicates) and male ESCs in S/L+PD (n=2 technical replicates).

(b) Quantification of relative RNA and protein levels of genes that facilitate DNA methylation between male ESCs in S/L (n=2 technical replicatges) and male ESCs in S/L+PD (n=2 technical replicates) (see Fig. 4d).

(c–d) Karyotype analysis of male ESCs cultured in S/L for 4 passages and subsequently cultured in either S/L+PD (c) or S/L+CHIR (d) for additional 16 passages. +Mar stands for chromosomal fragment of unknown origin. Red boxes indicate abnormal chromosomes detected.

(e) Western blot analysis of a Dnmt cTKO ESC line for Dnmt1, Dnmt3a and Dnmt3b after treatment with either 4-OHT or EtOH for one passage.

(f) Karyotype analysis of a Dnmt cTKO ESC line that was treated with either 4-OHT or EtOH for one passage and subsequently cultured for 15 passages in S/L.