No evidence for association of multiple sclerosis with the complement factors C6 and C7

Four genome screens in multiple sclerosis have been completed and each has identified evidence for linkage in the pericentromeric region of chromosome 5. This region encodes a number of candidate genes including those for the complement components C6, C7 and C9. We have used a multiplexed oligoligat ion assay (OLA) to test single nucleotide polymorphisms (SNPs) from the CG and CT genes for evidence of association with multiple sclerosis in our sib ling pair families. There was no statistically significant difference in th e allele frequencies of these polymorphisms in the index cases from our fam ilies when compared with locally derived controls. No evidence for transmis sion distortion was seen with any of the polymorphisms, or with the haploty pe built from the three SNPs from the CT gene. Despite offering themselves as potential candidates these complement genes appear not to confer suscept ibility to multiple sclerosis. (C) 1999 Elsevier Science B.V. All rights re served.