This study from the UK looked at gene-environment interactions in MS.
The researchers looked at the interaction between HLA-DRB1*15 (DRB1-15) and history of infectious mononucleosis (IM). They found that individuals exposed to both factors were at an increased risk of disease. Both DRB1-15 and IM status were independent predictors of disease, while there interaction term was not, but interaction on an additive scale was evident.
Based on this, if the additive model is appropriate, the DRB1-15 and IM may be part of the causal process leading to MS. This study demonstrates the importance of reporting gene-environment interactions on both a multiplicative and additive scale.
Authors: Disanto G, Hall C, Lucas R
Source: Mult Scler. 2013 Feb 14. [Epub ahead of print]
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