Germs Influence CNS Inflammation ? Part 1 . How Genetic Factors Influence Neuroinflammation ?

Multiple Sclerosis (MS) is a complex, inflammatory and demyelinating disease of the central nervous system (CNS), and both genetic and environmental factors are implicated in disease development. Associations with susceptibility loci in the Human Leukocyte Antigen (HLA) region were identified already in the 1970’s, and more recently, large-scale genome screens have revealed that more than 200 non-HLA single nucleotide polymorphisms (SNPs) are also associated with MS risk. An overrepresentation of immunologically relevant genes, in particular genes important for T helper cell differentiation, has been observed. Still, there is sparse knowledge about the functional mechanisms that underlie the associations with the genetic risk variants in MS. Further studies need to consider the genetic architecture of the region surrounding the most highly associated SNPs, the molecular pathways and cell types that are involved and the epigenetic factors which might trigger MS onset or be of importance for development of different MS phenotypes. This includes MS phenotypes identified by MRI scanning of CNS and biomarkers in body fluids as well as treatment responses to the growing number of effective immune-modulatory treatments. Through such studies, methods for personalized treatment and follow-up of MS patients can probably soon be established.