 The NSD1 gene provides instructions for making a protein that is involved in normal growth and development.Deletions and mutations in the NSD1 gene is a common cause for patients with Sotos syndrome and in some cases for Weaver syndrome as well.Features distinguishing Weaver syndrome from Sotos syndrome include broad forehead and face, ocular hypertelorism, prominent wide philtrum, micrognathia, deep-set nails, retrognathia with a prominent chin crease, increased prenatal growth, and a carpal bone age that is greatly advanced compared to metacarpal and phalangeal bone age.