Average number of teeth in WT, heterozygous (Het), treated, and untreated XLHED dogs. (A) Deciduous teeth. (B) Adult teeth. Gray circles in the XLHED group indicate dogs coming from an independent experiment and included in the statistical analysis. In the untreated and treated XLHED groups, identical symbols (black upright triangles, inverted triangles, circles, diamonds, or squares) indicate the same animal in (A and B). Values are the mean ± S.E.M. A one-sample t test first assessed whether the average number of teeth in XLHED dogs differed from normal (28 in pups, 42 in adults). Thereafter, groups of treated dogs were compared with untreated XLHED dogs by one-way ANOVA with Dunnett’s multiple-comparison test. nsP > 0.05; ****P < 0.0001.