QUOTE : As strange as it sounds, it is no longer possible to determine how many human genomes have been sequenced. At present the strategy of choice is whole-genome re-sequencing (Chapter 3) whereby next-generation sequence data are mapped onto a reference genome. The results have been breathtaking. The recently concluded (and aptly named) 1000 Genomes Project Consortium catalogued ~85 million SNPs, 3.6 million short insertions/deletions, and 60,000 larger structural variants in a global sampling of human genetic diversity. These data are catalysing research in expected and unexpected ways. Beyond providing a rich source of data for GWA-type studies focused on disease, scientists are also using the 1000 Genomes Project data to learn about our basic biology, something that proved surprisingly difficult when only a pair of genomes was available. For example, a recent GWAS taking advantage of the 1000 Genomes Project data identified ten genes associated with kidney development and function, genes that had previously not been linked to this critical aspect of human physiology. In 2016, Craig Venter’s team reported the sequencing of 10,545 human genomes. Beyond the impressively low cost (US$1,000–2,000 per genome) and high quality (30–40× coverage), the study was significant in hinting at the depths of human genome diversity yet to be discovered. More than 150 million genetic variants were identified in both coding and non-coding regions of the genome; each sequenced genome had on average ~8,600 novel variants. Furthermore, each new genome was found to contain 0.7 Mbp of sequence that is not contained in the reference genome. This underscores the need for methods development in the area of structure variation detection in personal genome data. Overall, however, the authors concluded that ‘the data generated by deep genome sequencing is of the quality necessary for clinical use’.