Tukey style boxplots of the mean standardized gene expression levels (Z-score) in three female groups for the X chromosome genes whose individual standardized expressions are shown in Additional file 1 : Fig. S4. XIST has been excluded in the boxplots. Gene expression increased for X chromosome genes with more bi-allelic expression (paired t -test, group 1 – group 2: p -value = 1.67 x 10 –21 , group 2 – group 3: p -value = 3.40 x 10 –16 , group 3 – group 1: p -value = 6.70 x 10 –26 ).
