We tested 11 microsatellite markers for evidence of transmission distortion in 744 trio families with multiple sclerosis. Ten of the markers lie within or near to candidate genes selected on the basis that they map within the regions of potential linkage identified in our previously reported linkage genome screen, while the eleventh is an anonymous marker which had previously shown modest evidence for transmission distortion in our sibling pair families. Only the marker related to the myeloperoxidase (MPO) gene revealed tentative evidence for linkage disequilibrium and further work on this gene is clearly needed in order to resolve the status of this region in conferring susceptibility to multiple sclerosis.