This is the eighth of a series of reviews, looking back at a year of science according to topic and theme. This is about the unexpectedly dynamic world of genes, including some that jump around their host genomes, others that infiltrate new species, and yet others that change in surprisingly constrained ways.
12) I am virus – animal genomes contain more fossil viruses than ever expected
Your genome is full of fossils, the remains of ancient viruses that shoved their genes into those of your ancestors. This year, we learned that this genetic infiltration was far more extensive than anyone had realised. By screening 44 animal genomes of 44 species, Aris Katzourakis and Robert Gifford found fossils representing 11virus families, including ancient relatives of influenza, Ebola, hepatitis B and rabies. Most of these “endogenous viral elements” or EVEs are broken and fragmented, but some have been domesticated and probably play an active role in their new hosts. The EVEs can tell us about what ancient viruses were like, about which modern animals act as reservoirs for today’s killers, and even about viruses that jumped from one host to another.
