title: Genetic variants of properdin factor B (Bf) in rheumatoid arthritis.
abstract: Properdin factor B (Bf) phenotyping was carried out in 392 patients with rheumatoid arthritis (RA) and in 360 controls. In RA there were increased frequencies of both the Bf*S gene (83 vs 78%; pc = 0.0003) and the BfSS genotype 73 vs 61%; pc = 0.0002) and reduced frequencies of the Bf*F1 gene (0.5 vs 2.2%; pc = 0.03) and the BfFS genotype (20 vs 29%; pc = 0.0007). The frequencies of Bf*S in DR4 positive and DR4 negative RA were similar so that the findings were not accounted for by linkage disequilibrium between DR4 and Bf*S.
mesh_terms: D001172:Arthritis, Rheumatoid / Q000097:blood / Q000235:genetics*; D011415:Complement Factor B / Q000235:genetics*; D004792:Enzyme Precursors / Q000235:genetics*; D005787:Gene Frequency; D008040:Genetic Linkage; D005819:Genetic Markers; D014644:Genetic Variation; D005838:Genotype; D015804:HLA-DR4 Antigen; D000949:Histocompatibility Antigens Class II / Q000235:genetics; D006801:Humans
chemical_list: D004792:Enzyme Precursors; D005819:Genetic Markers; D015804:HLA-DR4 Antigen; D000949:Histocompatibility Antigens Class II; D011415:Complement Factor B