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Timothy syndrome, atypical type

MedGen UID:
Concept ID:
Disease or Syndrome
Synonyms: ATS; Atypical long QT syndrome type 8; Atypical LQT8; Atypical Timothy syndrome; atypical Timothy syndrome; Timothy syndrome atypical type; Timothy syndrome type 2 (disorder)
SNOMED CT: Atypical long QT syndrome type 8 (1230097004); Atypical Timothy syndrome (1230097004); Timothy syndrome atypical type (1230097004)
Monarch Initiative: MONDO:0021172
Orphanet: ORPHA595109


A rare multiple congenital anomalies syndrome with cardiac involvement as a major feature with characteristics of QT prolongation, congenital heart defects, syndactyly, facial dysmorphism and neurodevelopmental features. The atypical form (ATS) causes multi-system health concerns but not necessarily with prolonged QT. The disease can be recognised by any CACNA1C change (excluding the G406R change) that causes multi-system health concerns. [from SNOMEDCT_US]

Term Hierarchy

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

Recent clinical studies


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
Fröhler S, Kieslich M, Langnick C, Feldkamp M, Opgen-Rhein B, Berger F, Will JC, Chen W
BMC Med Genet 2014 Apr 29;15:48. doi: 10.1186/1471-2350-15-48. PMID: 24773605Free PMC Article

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