Sexually dimorphic gene expression in the SI and colon of 2-week-old C57BL/6 mice. (A) PCA of the top 1,000 most variable genes present in the SI or the colon separates the SI from the colon by PC1 and males from females by PC2. (B) In the SI and the colon, 275 and 86 genes displayed significant (p < 0.01) sexually dimorphic expression, respectively. (C) Four of the significant sexually dimorphic genes revealed male-dominant expression in both the SI and colon while seven genes showed female-dominant expression in both intestinal segments. (D) Expression levels of the seven female-dominant genes in the SI and colon in all individual male and female mice. Correlation between male and female expression levels of the (E) 275 sexually dimorphic genes in the SI and (F) 86 sexually dimorphic genes in the colon. (G) The FC difference between males and females is very low for the majority of the sexually dimorphic genes. Chromosomal localization of the sexually dimorphic genes in the (H) SI and (I) colon relative to the total number of genes localized on each chromosome in the total selection of 10,958 included in the analysis. *p < 0.01, **p < 0.001, ***p < 0.0001.