Symptoms and Diagnosis Angelman’s syndrome, which affects 1 in 20,000 births (indifferently both sexes), is characterized by delayed psychomotor development, mental retardation, impaired balance and coordination (ataxia), and walking unstable. In 100% of the cases, the “Angelman” have a joyous appearance: they have easy and frequent laughter and hyperexcitability accompanied by a certain motor agitation. An agitation […]