AIM: Nuclear receptor-binding SET domain-containing protein 1 (NSD1) gene mutations and deletions (NSD1+/-) are the major cause of Sotos syndrome. The aim was to investigate which auxology parameters relate to NSD1+/- in patients clinically suspected of Sotos syndrome. METHODS: In 32 patients clinically suspected of Sotos syndrome, we compared auxology parameters between NSD1+/- patients and patients without NSD1 gene alterations (NSD1+/+). The statistical performance of these parameters to predict NSD1+/- was assessed. RESULTS: Arm span-for-height standard deviation score (SDS) and hand length SDS were significantly higher in NSD1+/- patients. CONCLUSION: Arm span for height and hand length are discriminating parameters between NSD1+/- and NSD1+/+.