is a type of long QT syndrome. It affects many parts of the body including the heart, fingers, toes, face, and the nervous system. It is characterized by long QT syndrome, although some people with Timothy syndrome also have other heart defects that affect the heartÕs ability to pump blood effectively. Other symptoms of Timothy syndrome include fusion of the skin between fingers or toes and distinctive facial features. In addition, many children with this syndrome have developmental delay and characteristic features of autism. Mental retardation and seizures can also occur in children with Timothy syndrome.
There are two forms of Timothy syndrome. Type 1 includes all of the characteristic features described. Type 2 causes a more severe form of long QT syndrome and does not appear to cause fusion of skin between fingers or toes. All cases of Timothy syndrome appear to be due to changes in the CACNA1C gene. This syndrome is inherited in an autosomal dominant manner. However, most cases are not inherited from an affected parent, but occur for the first time in a family due to a spontaneous or random change in the CACNA1C gene. Source: Genetic and Rare Diseases Information Center (GARD), supported by ORDR-NCATS and NHGRI.