Bf and C4 phenotypes in patients with psoriasis
Wyatt, R.J.; Wang, C.; Hudson, E.C.; Jones, R.M.; Noah, P.W.; Rosenberg, E.W.
Acta Dermato-Venereologica. Supplementum 146: 211-213
1989
ISSN/ISBN: 0365-8341 PMID: 2609873 Document Number: 337423
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.