Properdin factor B (Bf) polymorphism in Saudi Arabs. High frequency of a 'rare' allele BfS0.7

The distribution of properdin factor B (Bf) phenotypes and the gene frequencies were investigated in 918 Saudi Arabs. A high frequency of the 'rare' allele BFS0.7 was observed BfS0.7 = 0.1514). The frequencies of the common Bf alleles (BfS = 0.5174, BfF = 0.3213) are outside the corresponding ranges of BfS, BfF gene frequencies found in European Caucasoids.