title: Association of complement alleles C4AQ0 and C4B5 with rheumatoid arthritis in Japanese patients.
abstract: We investigated polymorphisms of complement components C2, C4, and factor B (BF) in Japanese patients with rheumatoid arthritis (RA). The frequencies of C4AQ0 (32.1%) and C4B5 (35.9%) among RA patients were significantly higher than among healthy control subjects. C4B5 was strongly associated with HLA-Bw54, Bw59, DR4.1, and DQw4. C4AQ0 showed no association with HLA-Bw54 or Bw59, but there was weak association with HLA-DR4.1 and DQw4. The number of persons with both C4AQ0 and C4B5 was significantly higher in the RA patient group (relative risk 13.5). C2C and BFS were the most common alleles in RA patients, as well as in healthy control subjects. These data support the existence of 2 different putative susceptibility haplotypes (HLA-Bw54 or Bw59;C2C; BFS;C4A3;C4B5;DR4.1;DQw4 and C2C;BFS; C4AQ0;C4B1 or C4B2) in Japanese patients with RA.
authors.affiliation: Department of Medicine, Faculty of Medicine, University of Tokyo, Japan.
authors.forename: F
authors.initials: F
authors.lastname: Takeuchi
authors.forename: A
authors.initials: A
authors.lastname: Mimori
authors.forename: K
authors.initials: K
authors.lastname: Matsuta
authors.forename: K
authors.initials: K
authors.lastname: Nakano
authors.forename: T
authors.initials: T
authors.lastname: Miyamoto
authors.forename: K
authors.initials: K
authors.lastname: Matsuki
authors.forename: T
authors.initials: T
authors.lastname: Juji
authors.forename: H
authors.initials: H
authors.lastname: Maeda
authors.forename: K
authors.initials: K
authors.lastname: Omoto
authors.forename: K
authors.initials: K
authors.lastname: Tokunaga
mesh_terms: D000483:Alleles; D001172:Arthritis, Rheumatoid / Q000097:blood / Q000235:genetics*; D003175:Complement C2 / Q000235:genetics; D003181:Complement C4 / Q000235:genetics*; D011415:Complement Factor B / Q000235:genetics*; D004792:Enzyme Precursors / Q000235:genetics*; D005787:Gene Frequency; D006239:Haplotypes; D006650:Histocompatibility Testing; D006801:Humans; D007564:Japan; D010375:Pedigree; D010641:Phenotype; D012150:Polymorphism, Restriction Fragment Length
chemical_list: D003175:Complement C2; D003181:Complement C4; D004792:Enzyme Precursors; D011415:Complement Factor B