Lately “good bacteria” have been getting a lot attention in the media, as scientist uncover the role the microbiome plays in our healthy bodies, the soil that grows our food, and even the rain clouds above. It may come as no surprise, then, that some viruses can also be good for people. In fact, a recent study has uncovered a link between viral sequences in human DNA and normal brain circuit development. It turns out that viruses may help us become smarter.
The researchers at Lund University in Sweden looked at how neural stem cells decide which of their many gene sequences to express. Retroviral DNA, they discovered, played an important role in which areas of nerve cell DNA are expressed and which are silent. These retroviral DNA sections are inherited. In other words, a virus at some point infected a human ancestor, and the DNA it left behind now helps neural cells work for the future generations.
This research adds to the growing body of understanding of harmless (possibly even helpful) viruses in human health. Further research may even lead to a fundamental shift in thinking about viruses in general.
By Loreli Marie Bratton