title: Bf and C4 phenotypes in patients with psoriasis.
abstract: Phenotype frequencies for the complement proteins Bf (factor B), C4A and C4B were performed in a sample of 49 Caucasian patients with psoriasis followed in Memphis, Tennessee. The genes for these proteins are located in the major histocompatibility complex between the HLA-B and HLA-DR loci. Bf phenotype frequency did not differ significantly for the patients as compared to regional controls. The C4*A6 allele was present in 26.6% of the patients as compared to 5.4% of the controls, p less than 0.001, relative risk = 4.93. The C4*A6 allele is known to be in linkage disequilibrium with the HLA B17 allele and produces a functionally defective gene product. The role, if any, of C4*A6 in the pathogenesis of psoriasis is uncertain.
authors.affiliation: Department of Pediatrics, University of Tennessee, Memphis.
authors.forename: R J
authors.initials: RJ
authors.lastname: Wyatt
authors.forename: C
authors.initials: C
authors.lastname: Wang
authors.forename: E C
authors.initials: EC
authors.lastname: Hudson
authors.forename: R M
authors.initials: RM
authors.lastname: Jones
authors.forename: P W
authors.initials: PW
authors.lastname: Noah
authors.forename: E W
authors.initials: EW
authors.lastname: Rosenberg
mesh_terms: D003181:Complement C4 / Q000235:genetics*; D011415:Complement Factor B / Q000235:genetics*; D004586:Electrophoresis / Q000379:methods; D004792:Enzyme Precursors / Q000235:genetics*; D006801:Humans; D010641:Phenotype; D011565:Psoriasis / Q000235:genetics*
chemical_list: D003181:Complement C4; D004792:Enzyme Precursors; D011415:Complement Factor B