title: Two BF*F subtypes found by isoelectric focusing have restricted distributions in the Finnish MHC haplotypes.
abstract: The factor B (BF) polymorphism revealed by immunofixation of plasma samples is made up of more than 20 variants, of which 2 variants are common, S and F, 2 less common, F1 and S07, and the rest of the variants are very rare. In this work we have adapted a rapid method to subdivide the BF*F allele into *FA and *FB by IEF in nontoxic agarose gel. The FA subtype manifested as two major bands and FB as one band both in native and desialylated samples. *F1, *S and *S07 were shown as monomorphic proteins, but differ in their sensitivities to degradation caused by neuraminidase treatment. *FA and *FB showed restricted distributions among the HLA haplotypes of the homogenous Caucasoid Finnish population. *FA was positively associated with the haplotypes Cw3,Bw62,C4A3BQ0 (or A3B1) and *FB with the haplotypes A3,Cw4,B35,DR1,C4A3BQ0 (or A2BQ0, A3,2BQ0).
authors.affiliation: Finnish Red Cross Blood Transfusion Service, Helsinki.
authors.forename: M L
authors.initials: ML
authors.lastname: Lokki
authors.forename: S
authors.initials: S
authors.lastname: Koskimies
mesh_terms: D000483:Alleles; D003181:Complement C4 / Q000032:analysis; D011415:Complement Factor B / Q000235:genetics*; D004587:Electrophoresis, Agar Gel; D005387:Finland; D006680:HLA Antigens / Q000032:analysis; D006239:Haplotypes / Q000235:genetics*; D006801:Humans; D007126:Immunoglobulin Allotypes / Q000032:analysis; D007525:Isoelectric Focusing; D008285:Major Histocompatibility Complex / Q000235:genetics*; D009439:Neuraminidase; D010641:Phenotype; D011110:Polymorphism, Genetic / Q000235:genetics*
chemical_list: D003181:Complement C4; D006680:HLA Antigens; D007126:Immunoglobulin Allotypes; D009439:Neuraminidase; D011415:Complement Factor B