Risk conferring genes in multiple sclerosis.

Multiple sclerosis (MS) is characterized by inflammation, axonal and oligodendrocyte pathology and progressive neurological disability. Epidemiologic data indicate that MS may be caused by interplay of genetic and environmental factors. Large samples collected in cooperative efforts and new technologies such as high throughput single nucleotide polymorphism (SNP) genotyping allowed recently to discover non-HLA genes associated with MS susceptibility that are mostly involved in the immune response. In addition, several studies indicate an effect of genetic variations on disease onset, progression and response to therapy. However, the polymorphisms discovered so far explain the genetic variation in MS only in part and are mostly common variants that have only low impact on MS susceptibility. Functional studies are required to validate the importance of the newly identified SNPs. Taking into account the interplay of genetic and environmental factors a combination of genome wide genotyping including HLA-typing and genome wide expression profiling as well as a collection on relevant or putatively relevant environmental factors in patients well characterized clinically and by MRI is a promising way to identify new disease relevant biomarkers.