Risk alleles for multiple sclerosis identified by a genomewide study.
This paper by the International MS Genetics Consortium (IMSGC) is an important milestone, as it reported the discovery of common genetic variants of modest effect that are associated with MS susceptibility using a whole genome scan approach. It therefore provided robust evidence that (1) susceptibility alleles of this type exist outside of the MHC and (2) a genome scan strategy was appropriate for discovering such variants. It has therefore been the foundation for subsequent studies by the IMSGC and other groups of investigators that have gradually elaborated the genetic architecture of MS susceptibility. The model that the genetic component of MS susceptibility results from the contribution of risk alleles in many different genes is now well accepted. This study also provided an important illustration of the power of consortia of investigators in successfully exploring challenging questions in MS.