FIGURE 1.

Characterization of genomewide DNA methylation in newborn twins. A and B, Hierarchical clustering for opposite‐sex females (OSF) versus same‐sex females (SSF) (A), and opposite‐sex males (OSM) versus same‐sex males (SSM) (B) based on DNA methylation level at the top 3% CpG sites with the highest standard deviation. C, Violin‐box plots show the distribution of Pearson's correlation coefficients between genomewide DNA methylations of any two samples from different two groups of twins. The red dots are the arithmetic means. The p‐values between OSF versus SSM and SSF versus SSM, OSF versus OSM and SSFversus OSM, OSFversus SSM and OSF versus OSM, SSF versus SSM and SSF versus OSM, were shown and determined by Wilcoxon rank‐sum test.