(sotos syndrome) An autosomal dominant overgrowth syndrome caused by mutation(s) of the NSD1 or the NFIX gene, encoding H3 lysine-36 and H4 lysine-20 specific histone-lysine N-methyltransferase, and nuclear factor 1 X-type, respectively. The condition is characterized by a disproportionately large and long head with a slightly prominent forehead and pointed chin, hypertelorism, down-slanting eyes, large hands and feet, overgrowth in childhood, and developmental delay.

(sotos syndrome) Congenital or postnatal overgrowth syndrome most often in height and occipitofrontal circumference with variable delayed motor and cognitive development. Other associated features include advanced bone age, seizures, NEONATAL JAUNDICE; HYPOTONIA; and SCOLIOSIS. It is also associated with increased risk of developing neoplasms in adulthood. Mutations in the NSD1 protein and its HAPLOINSUFFICIENCY are associated with the syndrome.

Sotos syndrome is a condition characterized mainly by distinctive facial features; overgrowth in childhood; and learning disabilities or delayed development. Facial features may include a long, narrow face; a high forehead; flushed (reddened) cheeks; a small, pointed chin; and down-slanting palpebral fissures. Affected infants and...