SciLifeLab The Svedberg seminar series, Magnus Nordborg, Epigenetic variation in Arabidopsis thaliana


Monday, October 14, 2019

Magnus Nordborg

Gregor Mendel Institute in Vienna, Austria

Magnus Nordborg is a population and evolutionary geneticist, best known for his work on genome-wide association studies outside human, especially the 1001 Arabidopsis Genomes Project. He got his Phd at Stanford, did a postdoc at the University of Chicago, was professor at the University of Southern California, and is currently Director of the Gregor Mendel Institute in Vienna.

Title: Epigenetic variation in Arabidopsis thaliana

Epigenetics continues to fascinate, especially the notion that it blurs the line between “nature and nurture” and could make Lamarckian adaptation via the inheritance of acquired characteristics possible. That this is in principle possible is clear: in the model plant Arabidopsis thaliana (thale cress), experimentally induced DNA methylation variation can be inherited and affect important traits. The question is whether this is important in nature. Recent studies of A. thaliana have revealed a pattern of correlation between levels of methylation and climate variables that strongly suggests that methylation is important in adaptation. However, somewhat paradoxically, the experiments also showed that much of the variation for this epigenetic trait appears to have a genetic rather than an epigenetic basis. This suggest that epigenetics may indeed be important for adaptation, but as part of a genetic mechanism that is currently not understood. Genome-wide association studies revealed a striking genetic architecture of methylation variation, involving major-effect polymorphisms in many genes involved in silencing, and this can be  utilized to determine whether the global pattern of methylation variation has a genetic or an epigenetic cause, and to elucidate the ultimate cause of the global pattern of variation: natural selection.

 

Host: Leif Andersson