CpG methylation patterns are more masculine in XX + T than XX at PN60. Mean XX + T methylation of the sites that display sizable basal sex differences (delta methylation(XX-XY) ≥15%, p value ≤0.05) are plotted on a scale where 0 corresponds to XY and 100 corresponds to XX methylation levels. At the bottom of each histogram the first number in the box represents the number of masculinized sites (methylation scale ≤50) divided by the second number which is the number of total sites in the histogram. PN4 (a) and PN60 (c) striatum, PN4 (b), and PN60 BNST/POA (d). In both brain regions, the PN60 distribution was significantly different from PN4 (p value <2.20E − 16, Kolmogorov-Smirnov test).