Numbers of meibomian glands per centimeter of eyelid in WT, untreated heterozygous (Het), and XLHED dogs, and XLHED dogs treated in utero with Fc:EDA1 at the indicated embryonic developmental days (E32/45, E45, E55). Untreated WT (white circles) and heterozygous (black and white circles) dogs were pooled for the analysis. Values are the mean ± S.E.M. One-way ANOVA assuming Gaussian distribution, and comparing conditions to a control (WT or XLHED) with Dunnett’s multiple comparison test. nsP > 0.05; ***P < 0.001; ****P < 0.0001.