In human genomes, certain ancient viruses remain hidden and unnoticed, passed down through generations via foreign DNA. Genome biologist and senior author Edward Chuong stated, “Our study shows that diseases today can be significantly influenced by these ancient viral infections that until recently very few researchers were paying attention to.” Chuong explained that many of the switches turning on cancer-related genes are derived from these ancient viruses, and University of Colorado bioinformatician Atma Ivancevic’s team found that LTR10, a specific ERV family, acts as an epigenetic switch controlling these genes.