Supplementary Figure 6: Scatter plots showing the early lineage marker expressions in individual WT and Fgf4−/− ICM cells.

Each dot represents the expression of lineage markers in single blastomere, analysed by qPCR (33 cells from 4 embryos for E3.25 WT and 9 cells from one embryo for E3.25 Fgf4−/−, and 43 cells (21 and 22 cells for EPI and PrE, respectively) from 3 embryos for E3.5 WT and 8 cells from one embryo for E3.5 Fgf4−/−). The gene expression levels are normalised to that of Gapdh (x or y = 0). The colour code is the same as shown in Fig. 6a. In WT cells, each combination of two marker genes exhibits statistically significant correlation (E3.25: r = 0.35, p = 4×10−2 (Gata6 vs. Fgfr2); r = −0.46, p = 7×10−3 (Nanog vs. Fgfr2) and E3.5: r = −0.42, p = 5×10−3 (Nanog vs. Gata6); r = 0.54, p = 2×10−4 (Gata6 vs. Fgfr2); r = −0.66, p = 2×10−6 (Nanog vs. Fgfr2); Pearson’s correlation coefficient), except for Nanog vs. Gata6 at E3.25 (r = −0.07, p = 0.7). However, the correlation is lost in Fgf4−/− cells (E3.25: r = 0.34, p = 0.4 (Gata6 vs. Nanog); r = 0.01, p = 1 (Gata6 vs. Fgfr2); r = 0.30, p = 0.4 (Nanog vs. Fgfr2) and E3.5: r = 0.25, p = 0.5 (Nanog vs. Gata6); r = 0.05, p = 0.9 (Gata6 vs. Fgfr2); r = −0.04, p = 0.9 (Nanog vs. Fgfr2); Pearson’s correlation coefficient).