We and others previously showed that bi-allelic loss of function FAM20A mutations cause ERS (Martelli-Júnior et al., 2008; Jaureguiberry et al., 2012; Wang et al., 2013; de la Dure-Molla et al., 2014; Kantaputra et al., 2014). This evidence concerns the gene FAM20A and amelogenesis imperfecta type 1G.