SweGen : a whole-genome data resource of genetic variability in a cross-section of the Swedish population

Here we describe the SweGen data set, a comprehensive map of genetic variation in the Swedish population. These data represent a basic resource for clinical genetics laboratories as well as for sequencing-based association studies by providing information on genetic variant frequencies in a cohort that is well matched to national patient cohorts. To select samples for this study, we first examined the genetic structure of the Swedish population using high-density SNP-array data from a nation-wide cohort of over 10 000 Swedish-born individuals included in the Swedish Twin Registry. A total of 1000 individuals, reflecting a cross-section of the population and capturing the main genetic structure, were selected for whole-genome sequencing. Analysis pipelines were developed for automated alignment, variant calling and quality control of the sequencing data. This resulted in a genome-wide collection of aggregated variant frequencies in the Swedish population that we have made available to the scientific community through the website https://swefreq.nbis.se. A total of 29.2 million single-nucleotide variants and 3.8 million indels were detected in the 1000 samples, with 9.9 million of these variants not present in current databases. Each sample contributed with an average of 7199 individual-specific variants. In addition, an average of 8645 larger structural variants (SVs) were detected per individual, and we demonstrate that the population frequencies of these SVs can be used for efficient filtering analyses. Finally, our results show that the genetic diversity within Sweden is substantial compared with the diversity among continental European populations, underscoring the relevance of establishing a local reference data set

Mayr Versus Woese : Akaryotes and Eukaryotes

In 1998, on the brink of a great public effort that by now has delivered the sequences of thousands of genomes and has annotated these genomes by translating tens of thousands of 3D protein domain structures from their coding sequences, Ernst Mayr and Carl Woese engaged in a debate. At issue were the virtues of phenotypic contra genotypic approaches to phylogeny and taxonomy. Though not conclusive, this confrontation in retrospect illustrates the defects of both their perspectives and simultaneously illuminates the strengths of the approach to phylogenetic systematics that was favored by Willi Hennig. Hennig’s cladism lends itself well to a rigorous exploitation of genome sequence data in which both the genotypic and phenotypic modes replace the technically questionable gene tree approach to deep phylogeny championed by Woese. Diverse phylogenomic data now suggest that though Mayr’s phenetic arguments were incomplete, his division of organisms into two major taxonomic groups, the akaryotes (formerly the prokaryotes) and eukaryotes, is probably correct. Thus, in a phylogeny based on genome repertoires of protein domains, the universal common ancestor of the three superkingdoms descends in two primary lineages, Akaryote and Eukaryote