DNMT3A and Tatton-Brown-Rahman overgrowth syndrome: Germline heterozygous mutations in DNMT3A lead to Tatton-Brown-Rahman syndrome (TBRS; OMIM: 615879) (Tatton-Brown et al., 2014), a dominant disorder characterized by excessive height (~80% of individuals), intellectual disability (~80% of individuals), and obesity (~70% of individuals) (Tatton-Brown et al., 2014; Tatton-Brown et al., 2018).