TRAPPC9 and dentin dysplasia: Several clinical studies have reported gene variants, including EFNB1, MECP2, ATRX, NAA10, ANKRD11, ZNF699, TRAPPC9 and others associated with DD as significant causes of congenital growth retardation (Yan et al., 2019; Alvarez-Mora et al., 2021; Biela et al., 2022).