GTR Home > Conditions/Phenotypes > Fatal familial insomnia

Disease characteristics

Excerpted from the GeneReview: Genetic Prion Diseases
Genetic prion diseases generally manifest with cognitive difficulties, ataxia, and myoclonus (abrupt jerking movements of muscle groups and/or entire limbs). The order of appearance and/or predominance of these features and other associated neurologic and psychiatric findings vary. Familial Creutzfeldt-Jakob disease (fCJD), Gerstmann-Sträussler-Scheinker (GSS) syndrome, and fatal familial insomnia (FFI) represent the core phenotypes of genetic prion disease. Note: A fourth clinical phenotype, known as Huntington disease like-1 (HDL-1) has been proposed, but this is based on a single report, and the underlying pathologic features would categorize it as GSS. Although it is clear that these four subtypes display overlapping clinical and pathologic features, recognition of these phenotypes can be useful when providing affected individuals and their families with information about the expected clinical course. The age at onset ranges from the third to ninth decade of life. The course ranges from a few months to several years (typically 5-7 years; in rare instances, >10 years).

Available tests

3 tests are in the database for this condition. Compare labs offering these tests.

Check Associated genes and Related conditions for additional relevant tests.

Associated genes

  • Also known as: RP5-1068H6.2, ASCR, AltPrP, CD230, CJD, GSS, KURU, PRIP, PrP, PrP27-30, PrP33-35C, PrPc, p27-30, PRNP
    Summary: prion protein

Clinical features

  • Apnea
  • Fever
  • Hyperhidrosis
  • Urinary retention
  • Dysarthria
  • Neuronal loss in central nervous system
  • Dysphagia
  • Constipation
  • Insomnia
  • Diplopia
  • Dementia
  • Ataxia
  • Myoclonus
  • Weight loss
  • Dysautonomia
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