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Long QT syndrome 8

Other Names for this Disease
  • Long QT syndrome with syndactyly
  • LQT8
  • Timothy syndrome
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Timothy syndrome 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 heart’s ability to pump blood effectively.[1][2] 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.[1][2]

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.[1][2]
Last updated: 12/18/2008


  1. Timothy Syndrome. Genetics Home Reference. 2008; . Accessed 12/17/2008.
  2. Splawski I, Timothy KW, Priori SG, Napolitano C, Bloise R . Timothy syndrome. GeneReviews. 2006; Accessed 12/17/2008.
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Basic Information

  • Genetics Home Reference (GHR) contains information on Long QT syndrome 8. This website is maintained by the National Library of Medicine.
  • The National Organization for Rare Disorders (NORD) is a federation of more than 130 nonprofit voluntary health organizations serving people with rare disorders. Click on the link to view information on this topic.

In Depth Information

  • Medscape Reference provides information on this topic. Click on the link to view this information. You may need to register to view the medical textbook, but registration is free.
  • MeSH® (Medical Subject Headings) is a terminology tool used by the National Library of Medicine. Click on the link to view information on this topic.
  • The Online Mendelian Inheritance in Man (OMIM) is an catalog of human genes and genetic disorders. Each entry has a summary of related medical articles. It is meant for health care professionals and researchers. OMIM is maintained by Johns Hopkins University School of Medicine. 
  • Orphanet is a European reference portal for information on rare diseases and orphan drugs.  Access to this database is free of charge.
  • PubMed is a searchable database of medical literature and lists journal articles that discuss Long QT syndrome 8. Click on the link to view a sample search on this topic.

Selected Full-Text Journal Articles