title: Epidemiology of familial amyloid polyneuropathy in Japan: Identification of a novel endemic focus.
abstract: BACKGROUND
  Familial amyloid polyneuropathy (FAP) is distributed worldwide with several endemic foci including two major foci in Japan.
  
  
  OBJECTIVE
  To elucidate a nationwide epidemiology of FAP in Japan.
  
  
  METHODS
  (i) We analyzed the data of FAP patients registered by the Ministry of Health, Labour, and Welfare, Japan, during 2003-2005. (ii) As Ishikawa prefecture was found to be a novel endemic focus, we examined 27 FAP patients in Ishikawa to characterize their clinical and genetic features in comparison with other endemic foci.
  
  
  RESULTS
  (i) The prevalence of familial amyloidosis in Japan was estimated to be 0.87-1.1 per 1,000,000 persons. Nagano prefecture had the highest prevalence (11-15.5), followed by Kumamoto (10.1-10.3), and then Ishikawa (3.5-4.2). (ii) All the FAP patients in Ishikawa had transthyretin (TTR) type FAP; all the families had a TTR Val30Met mutation except one family with a Leu58Arg mutation. FAP with Val30Met mutation in Ishikawa was characterized by late onset, high penetrance, and moderate autonomic dysfunction.
  
  
  CONCLUSIONS
  Ishikawa prefecture is the third endemic focus of FAP in Japan. FAP with TTR Val30Met mutation in Japan can be classified to (i) early-onset and endemic (Nagano and Kumamoto), (ii) late-onset and endemic (Ishikawa), and (iii) late-onset and non-endemic types.
authors.affiliation: Department of Neurology and Neurobiology of Aging, Kanazawa University Graduate School of Medical Science, Ishikawa, Japan.
authors.forename: Yuko
authors.initials: Y
authors.lastname: Kato-Motozaki
authors.forename: Kenjiro
authors.initials: K
authors.lastname: Ono
authors.forename: Keisuke
authors.initials: K
authors.lastname: Shima
authors.forename: Akiyoshi
authors.initials: A
authors.lastname: Morinaga
authors.forename: Tomohiko
authors.initials: T
authors.lastname: Machiya
authors.forename: Ichiro
authors.initials: I
authors.lastname: Nozaki
authors.forename: Ayumi
authors.initials: A
authors.lastname: Shibata-Hamaguchi
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Furukawa
authors.forename: Daisuke
authors.initials: D
authors.lastname: Yanase
authors.forename: Chiho
authors.initials: C
authors.lastname: Ishida
authors.forename: Kenichi
authors.initials: K
authors.lastname: Sakajiri
authors.forename: Masahito
authors.initials: M
authors.lastname: Yamada
mesh_terms: D000328:Adult; D017668:Age of Onset; D000368:Aged; D028227:Amyloid Neuropathies, Familial / Q000453:epidemiology* / Q000235:genetics* / Q000378:metabolism; D000686:Amyloidosis / Q000378:metabolism; D005260:Female; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D008715:Methionine / Q000235:genetics; D008875:Middle Aged; D017720:Molecular Epidemiology; D009154:Mutation; D011228:Prealbumin / Q000235:genetics*; D012042:Registries; D012189:Retrospective Studies; D014633:Valine / Q000235:genetics
chemical_list: D011228:Prealbumin; D008715:Methionine; D014633:Valine