A meta-analysis of whole genome linkage screens in multiple sclerosis.

Linkage studies in complex diseases like multiple sclerosis, where the effects attributable to individual loci are modest, are critically dependent upon the number of families included. We have combined the raw genotyping data from all published genome linkage screens in multiple sclerosis and thereby performed a linkage analysis including 719 families studied with a weighted average of 359 microsatellite markers per family (range 257-453) providing an average marker separation of 10.2 cM. Linkage with genome-wide significance is confirmed in the HLA region on chromosome 6p21. In addition, two novel regions suggestive of linkage are seen (17q21 and 22q13). Our simulations would imply that the number of peaks with NPL scores >/=2.1 exceeds the number expected by chance alone.