NOTUM and dentin dysplasia: In our analysis, Notum was enriched in the odontoblast cluster with a similar distribution of Dspp and Dmp1. Notum suppresses the Wnt activity (Kakugawa et al., 2015), and its null mutant showed dentin dysplasia with a porous dentin matrix formation with constricted dental pulp (Vogel et al., 2016).