To date, the strongest genetic association in MS is located within
the major histocompatibility complex (MHC) class II region. In this
study they carried out a protein-protein interaction analysis of gene
products coded in loci recently reported to be MS associated at the
genome-wide significance level and in loci suggestive of MS association.
Using a program that looks for significant protein-protein interactions
reported in the scientific literature they showed that gene products
coded in loci strongly associated with MS risk substantially interact
with each other, and with gene products coded in loci suggestive of MS
association. Both direct and indirect interactions were significantly
higher than what would be expected by chance only. The number of genes
involved in the network was 43, of which 23 were located in suggestive
regions. They looked at the expression of these genes in different
tissue types and found the highest values among immune-mediated cells
when compared to non-immune tissues.
Overall, this suggests that at
least some of the loci suggestive of MS association interact with and
have similar function as those significantly associated. This shows us
that more common variants remain to be found to be associated to MS.
Authors: Ragnedda G, Disanto G, Giovannoni G
Source: PLoS One. 2012;7(10):e46730. doi: 10.1371/journal.pone.0046730. Epub 2012 Oct 18.
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