Properdin factor B (Bf) as an exclusion determinate in parentage testing

Properdin factor B (Bf) was phenotyped on 519 paternity cases. Gene frequencies of BfF = 0.1870, BfF1 = 0.0105, BfS = 0.7985 and BfSO.7 = 0.0040 were observed in Minnesota Whites. Based on these values the exclusion probability is (p) = 0.1442. Bf accounted for 15% of the 88 observed exclusions. A technique is described for simultaneous electrophoresis of Bf and Gc on the same gel.