NSD1 and Sotos syndrome: Although Sotos syndrome was suspected based on overgrowth at birth, global developmental delay, and facial features (e.g., broad forehead, downslanting palpebral fissures, small nose, short philtrum, and pointed chin) (Fig. 1A–D), fluorescence in situ hybridization revealed no 5q35 microdeletion encompassing NSD1. The proband first experienced otitis media at the age of 2 years.