Skoltech scientists Anastasia Stolyarova, Anna Fedotova and Georgii Bazykin have co-authored a paper “Complex fitness landscape shapes variation in a hyperpolymorphic species” that has been recently published in eLife. The researchers study large-scale properties of the fitness landscapein a fungus Schizophyllum commune, the most polymorphic species known. They reveal many unusual properties of this organism. For instance, throughout the genome, short-range linkage disequilibrium (LD) caused by attraction of minor alleles is higher between pairs of nonsynonymous than of synonymous variants. This effect is especially pronounced for pairs of sites that are located within the same gene, especially if a large fraction of the gene is covered by haploblocks, genome segments where the gene pool consists of two highly divergent haplotypes, which is a signature of balancing selection. Haploblocks are usually shorter than 1000 nucleotides, and collectively cover about 10% of the S. commune genome. Full text of the article is available here.