Sotos syndrome (cerebral gigantism) is a rare genetic disorder caused by mutation in the NSD1 gene on chromosome 5. It is characterized by excessive physical growth during the first few years of life. Children with Sotos syndrome tend to be large at birth and are often taller, heavier, and have larger heads (macrocrania) than is normal for their age. Symptoms of the disorder, which vary among individuals, include a disproportionately large and long head with a slightly protrusive forehead and pointed chin, large hands and feet, hypertelorism (an abnormally increased distance between the eyes), and down-slanting eyes. The disorder is often accompanied by mild cognitive impairment; delayed motor, cognitive, and social development; hypotonia (low muscle tone), and speech impairments. Clumsiness, an awkward gait, and unusual aggressiveness or irritability may also occur. Although most cases of Sotos syndrome occur sporadically (meaning they are not known to be inherited), familial cases have also been reported.
There is no standard course of treatment for Sotos syndrome. Treatment is symptomatic.
Sotos syndrome is not a life-threatening disorder and patients may have a normal life expectancy. The initial abnormalities of Sotos syndrome usually resolve as the growth rate becomes normal after the first few years of life. Developmental delays may improve in the school-age years, and adults with Sotos syndrome are likely to be within the normal range for intellect and height. However, coordination problems may persist into adulthood.
The NINDS supports and conducts a wide range of studies which focus on identifying and learning more about the genes involved in normal brain development. The knowledge gained from these fundamental studies provides the foundation for understanding how this process can go awry and, thus, may eventually give clues to understanding disorders such as Sotos syndrome. Information from the National Library of Medicine’s MedlinePlusCraniofacial Abnormalities
Sotos Syndrome Support Association
P.O. Box 4626
Wheaton, IL 60189
Non-profit organization that offers an information clearinghouse and support network for families affected by Sotos Syndrome, or cerebral gigantism.
The Arc of the United States
1825 K Street, NW
Washington, DC 20006
Promotes and protects the human rights of people with intellectual and developmental disabilities and actively supports their full inclusion and participation in the community throughout their lifetimes.
Information sourced through CNF’s partnership with The National Institute of Neurological Disorders and Stroke (NINDS), US National Institutes of Health.