APA Dictionary of Psychology

a historical term for an extremely rare genetic disorder characterized by intellectual developmental disorder, lack of normal muscle control, and speech difficulty. Lenses and corneas may be normal, but the eyes lack or have only partial irises. It is thought to be caused by heterozygous mutation in the PAX6 gene on chromosome 11p13. Also called Gillespie syndrome. [first described in 1965 by U.S. ophthalmologist Frederick D. Gillespie (1927–  )]