Polymorphism of properdin factor B in Japanese. Description of a rare variant and data of association with HLA and C2

Abstract

Polymorphism of the properdin factor B (BF) was investigated using an agarose gel immunofixation electrophoresis in 487 unrelated healthy adult Japanese who were already typed for HLA-A,-B,-C, and C2. Besides the previously reported phenotypes in Japanese (S, FS, and F), a rare heterozygous phenotype (tentatively maned FTS) was observed once. The estimated allele frequencies for BS ^* S, BF ^* F, and BF ^* FT (F Tokyo) were 0.801, 0.198, and 0.001, respectively. The relative electrophoretic mobility of the variant band of type FTS was measured by Dr. G. Mauff to be F 0.75. The conversion fragment Bb of the type showed a double-banded pattern. BF hemolytic activity of the FTS individual was at the same level as other phenotypes. Statistical tests for the phenotypic data of BF with HLA-A,-B,-C, and C2 indicated the presence of the following significant associations in Japanese: Aw33-BF ^* F, A11-BF ^* S, Aw24-BF ^* S, B15-BF ^* F, B17-BF ^* F, Bw44-BF ^* F, B7-BF ^* S, Bw52-BF ^* S, Bw54-BF ^* S, Bw59-BF ^* S, Cw3-BF ^* F, C2 ^* AT-BF ^* F, and C2 ^* A′-BF^*F.