Chromatin loop anchors seem to be a basic unit of the physical organisation of the human genome, providing stable architectural sites within the nucleus, and influencing gene expression. Vera’s work exploring the strange mutational landscape at loop anchors shows that these sites are also unusually fragile: showing high rates of DNA double strand breaks in vitro and elevated rates of breakage in a variety of tumours. Unexpectedly a substantial fraction of loop anchors also coincide precisely with human recombination hotspots (HS_LAPs below), establishing these sites as foci for evolutionary change in mammalian evolution as well as during tumourigenesis.
Average human recombination rates within 500 kb of recombination hotspots (HSs), the subset of LAPs overlapping HSs (HS_LAPs) and all LAPs. Recombination rates were derived from the worldwide whole genome sequencing data of the 1000 Genomes Project.