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Timothy syndrome type 2

MedGen UID:
Concept ID:
Disease or Syndrome
Synonyms: LQT8 type 2; TS2
SNOMED CT: Timothy syndrome type 2 (719907006)
Monarch Initiative: MONDO:0035679
Orphanet: ORPHA595105


Timothy syndrome is a multi-system disorder with characteristics of cardiac, hand, facial and neurodevelopmental features that include QT prolongation, webbed fingers and toes, flattened nasal bridge, low-set ears, small upper jaw, thin upper lip, and characteristic features of autism or autistic spectrum disorders. Timothy syndrome is caused by mutations in the CACNA1C gene. It is inherited as autosomal dominant trait. Researchers have identified two forms of Timothy syndrome. Type 1, which is also known as the classic type, includes all of the characteristic features described above. Type 2, or the atypical type, causes a more severe form of long QT syndrome and a greater risk of arrhythmia and sudden death. Unlike the classic type, the atypical type does not appear to cause webbing of the fingers or toes. [from SNOMEDCT_US]

Term Hierarchy

CClinical test,  RResearch test,  OOMIM,  GGeneReviews,  VClinVar  
  • CROGVTimothy syndrome type 2

Recent clinical studies


Diep V, Seaver LH
Am J Med Genet A 2015 Nov;167A(11):2780-5. Epub 2015 Jul 31 doi: 10.1002/ajmg.a.37258. PMID: 26227324
Hiippala A, Tallila J, Myllykangas S, Koskenvuo JW, Alastalo TP
Am J Med Genet A 2015 Mar;167A(3):629-34. doi: 10.1002/ajmg.a.36924. PMID: 25691416


Hermida A, Jedraszak G, Kubala M, Bourgain M, Bodeau S, Hermida JS
Rev Esp Cardiol (Engl Ed) 2022 May;75(5):447-448. Epub 2021 Nov 26 doi: 10.1016/j.rec.2021.11.003. PMID: 34844894

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