title: HLA-B27 and its subtypes in 4 Taiwanese Aborigine tribes: a comparison to Han Chinese patients with ankylosing spondylitis.
abstract: OBJECTIVE
  We surveyed B27 and its subtypes in 5 ethnic groups in Taiwan.
  
  
  METHODS
  Blood was obtained from 281 Aborigine people of the Atayal tribe (I-Lan), 141 Paiwan (Ping-Ton), 38 Rukai (Ping-Ton), and 40 Yami (Orchid Island), and also 47 B27+ healthy Han Chinese subjects and 82 B27+ Han patients with ankylosing spondylitis (AS). HLA-B27 and its subtypes were determined by standard methods.
  
  
  RESULTS
  A much higher prevalence of B27 was found among the Atayal Aborigines (9.2%), which was significantly different from a lower prevalence in the Paiwan (2.1%; p = 0.004) and even higher than that of Han Chinese (5.59%; p = 0.04). No blood sample from the 38 Rukai Aborigines showed any B27. B2704 was the only subtype (100%) found in the 28 healthy Aborigines and 2 Aborigine patients with AS. However, in Chinese subjects, 40 of 47 (85%) B27+ healthy subjects were B2704, and 7 of 47 (15%) were B2705. In Chinese B27+ AS patients, 77 of 82 (94%) were B2704 and 5 of 82 (6%) were B2705. No other subtypes were found. Only the Aborigines without AS carrying B2704 showed a significant difference from the Chinese without AS carrying B2704 (p = 0.041).
  
  
  CONCLUSIONS
  The different prevalence of B27, but similar frequency of the B2704 subtype, between Aborigines and Han Chinese suggests Aborigines are a unique population and may originate from an Asian country, possibly mainland China.
authors.affiliation: Division of Allergy-Immunology-Rheumatology, Veterans General Hospital, Taipei, Taiwan. ctchou@vghtpe.gov.tw
authors.forename: Chung T
authors.initials: CT
authors.lastname: Chou
authors.forename: Jia M
authors.initials: JM
authors.lastname: Chen
authors.forename: Chang M
authors.initials: CM
authors.lastname: Hsu
authors.forename: Shu J
authors.initials: SJ
authors.lastname: Chen
mesh_terms: D044466:Asian People / Q000235:genetics*; D005787:Gene Frequency; D015796:HLA-B27 Antigen / Q000235:genetics*; D006801:Humans; D044469:Racial Groups; D013167:Spondylitis, Ankylosing / Q000208:ethnology / Q000235:genetics*; D013624:Taiwan / Q000453:epidemiology
chemical_list: D015796:HLA-B27 Antigen