Texas-based organization seeks to improve the quality of life of affected individuals. Read facts about genetics, and find out how to help.

Nat'l Org. for Rare Disorders addresses this abnormality, which is characterized by unusual facial features and mild to severe retardation.

Nat'l Org. for Rare Disorders details the abnormality in which the short arm of the 18th chromosome appears four times in the cells of the body.

Find basic info from the Nat'l Org. for Rare Disorders on this abnormality caused by a deletion of a piece of the long arm of chromosome 18.

Discusses the epidemiology, history, pathogenesis and clinical features of trisomy 18 syndrome.