GLO I [Glyoxylase I] phenotypes were determined in 1,075 unrelated West German individuals by starch gel electrophoresis. Gene frequencies were 0.4512 for GLO1 and 0.5488 for GLO2. Association studies between GLO I and Bf [properdin factor B] in 985 individuals of which Bf phenotypes were known from previous reports gave no significant evidence for close association between the 2 systems.