an X-linked recessive disease in which there is an excess of mucopolysaccharides in body tissues (see mucopolysaccharidosis). Almost exclusively affecting males, the disorder has two types, severe and attenuated. People with the severe type experience a decline in intellectual function and a rapid disease progression with short life expectancy. Individuals with the attenuated type typically live into adulthood and their intelligence is not affected. Heart disease and airway obstruction are major causes of death in people with both types of the disorder. Also called mucopolysaccharidosis Type II. [Charles Hunter (1872–1955), U.S. physician]