Evidence for a Linkage Group of the Polymorphic Complement Proteins C4, C2 and Factor B Related to the MHC of the Guinea Pig(GPLA) Free

Plasma probes of outbred and inbred strains of guinea pigs were investigated by agarose high voltage electrophoresis and isoelectrofocusing in PAGE for polymorphism of the complement proteins C4, C2 and factor B of the alternative pathway. In breeding experiments mode of inheritance and linkage to the GPLA system was studied. The polymorphic complement proteins C4 (with the allelic structural genes C4^F(fast), C4^S(alow), C4^S1 and C4^o(deficient)) factor B (with the common alleles Bf^F and Bf^S) and C2 (with the frequent alleles C2^B(basic), C2^A(acidic), and C2^A1) are closely linked together. In inbred strains haplotypes of the composition: C4^F-Bf^S-C2^A1 or alternatively C4^S or ^S1-Bf^F-C2^B were found. The mode of inheritance of C2^A and its linkage to C4 and Bf is a matter of further breeding studies. All three complement proteins are linked to the GPLA system as shown by family studies with well characterized and GPLA-typed inbred strains and outbred animals.