Symptoms vary among patients.
Although individuals with Williams syndrome may show competence in areas such as language, music, and interpersonal relations, their IQs are usually below average, and they are considered moderately to mildly retarded. Scientists have learned that most individuals with Williams syndrome have a deletion of genetic material on chromosome 7. This probably causes the physical and developmental problems experienced by patients. There is neither a cure for Williams syndrome nor a standard course of treatment. Treatment is symptomatic and supportive.