Nonlinkage between C6 and chromosome 6 markers.

C6 typing was performed in a family material by two different techniques: serum or plasma samples were subjected either to high-voltage agarose gel electrophoresis or to isoelectric focusing in polyacrylamide gel slabs. Proteins with C6 activity were then visualized by a specific, hemolytic assay. In 81 unrelated adults within the family material the following allele frequencies were found: C6A:0.61 and C6B:0.39. Linkage studies exclude linkage between C6 and HLA region marker loci, and also between C6 and another chromosome 6 marker locus PGM3.