Tatton-Brown-Rahman syndrome (TBRS;OMIM 615879), also known as the DNMT3A-overgrowth syndrome, is an overgrowth intellectual disability (OGID) syndrome first described in 2014 with a report of 13 individuals withde novo heterozygousDNMT3A variants1,2. This evidence concerns the gene DNMT3A and Tatton-Brown-Rahman overgrowth syndrome.