Genetic polymorphism of the sixth component of complement (C6) in dogs.

Using agarose gel isoelectric focusing and immunoblotting with rabbit anti-rabbit C6, a genetic polymorphism was found in the sixth component of complement (C6) in 18 Asian native breeds or populations and three European breeds of dog. The C6 locus was highly polymorphic. The phenotype distribution data indicated that dog C6 phenotypes were controlled by seven codominant alleles, C6A,C6B,C6C,C6D,C6E,C6F and C6G, at a single autosomal locus. Breed differences were observed among the gene frequencies, especially between Asian and European breeds. Two gene flows from the adjacent areas into Japanese native dogs were postulated.