We will continue the work on the Distribution of Fitness Effect of new mutations started in the previous SNIC project with three ongoing projects. First, we are using recent genomic data collected from seven tree species data to estimate joint DFE in pairs of populations. The main question here is to test whether the DFE varies between populations at the centre of the range of the species and populations on the edge of the range. Second, we use available data from polyploid species, to further test the effect of demography and genomic background on the DFE. The two subgenomes of a polyploid species have gone through the same demography since the origin of the polyploid species. However, they often originate from very different diploid parental species and we have shown that a parental legacy effect can still be detected on the amount of deleterious alleles accumulated in each subgenome after hundreds of thousand generations in neopolyploid species such as the shepherd’s purse (Capsella bursa-pastoris). Is this general, and does this extend to the whole DFE? Finally, in the same way that we conditioned estimation of the DFE on SIFT scores we plan to develop a method to condition estimation of the DFE on available information on Quantitative Trait Loci. The rationale here is that natural selection acts on fitness, which obviously is a quantitative trait, and therefore the properties of the DFE should be affected by the genetic architecture of quantitative traits.