Our finding of altered epigenetic outcomes in TBRS prompted us to consider similar investigations in other growth disorders associated with epigenetic dysfunction: Sotos syndrome, a neurodevelopmental disorder with features overlapping TBRS and with association with overgrowth in childhood owing to histone methyltransferase NSD1 gene alterations, and Kabuki syndrome, a distinct neurodevelopmental disorder associated with poor growth and histone methyltransferase KMT2D gene alterations. Here, NSD1 is linked to hereditary endocrine growth disease.