Molecular mechanisms of epistasis
This is an interesting new paper that discusses how molecular interactions might give rise to epistasis. The connection between biological and statistical epistasis is a very important question.
Lehner B. Molecular mechanisms of epistasis within and between genes. Trends Genet. 2011 [PubMed]
'Disease-causing' mutations do not cause disease in all individuals. One possible important reason for this is that the outcome of a mutation can depend upon other genetic variants in a genome. These epistatic interactions between mutations occur both within and between molecules, and studies in model organisms show that they are extremely prevalent. However, epistatic interactions are still poorly understood at the molecular level, and consequently difficult to predict de novo. Here I provide an overview of our current understanding of the molecular mechanisms that can cause epistasis, and areas where more research is needed. A more complete understanding of epistasis will be vital for making accurate predictions about the phenotypes of individuals.