Eight percent of the human genome is bornaviral in nature
Bornaviruses, a type of RNA virus that replicates inside the nucleus of host cells, has been found to be responsible for up to eight percent of the content of the human genome. Through endogenization, the virus’s DNA, retrotransposed from the RNA genome, has been integrated with our chromosomes over evolutionary time. Once the viral sequences are in the genome, they can be inherited through reproduction like any other part of the genome.
Due to the nature of bornavirus infections – they only infect neurons, the cells that comprise brain tissue – researchers have hypothesised that bornavirus genome integration could be the source of psychiatric disorders such as schizophrenia. A fascinating idea, but one that will have to be backed up with solid evidence in the future.
