Genetic Changes Made Zika Virus More Dangerous
After the virus jumped from Africa to Brazil, it underwent several mutations that make it more likely to attack the nervous system.
Over the last several years, Zika virus has become a serious threat to pregnant women, causing microcephaly and other neuropathies in developing fetuses. Zika virus is suspected of causing serious and irreversible birth defects to more than 6,000 Brazilian infants, making it a serious threat to public health. But Zika virus wasn’t always so nasty.
It was first discovered in monkeys in Uganda in 1949 and occasionally jumped to humans in Africa, but never caused birth defects. Somehow it jumped to Brazil and it did. Did the virus change genetically?
To find out, David Ussery and colleagues at the University of Arkansas for Medical Sciences in Little Rock examined 196 published Zika virus genomes from Africa, Asia, and Brazil to identify genetic changes that may have made the virus more virulent. The researchers found evidence that the virus adapted to a humans and a small number of other hosts, and as it did, its virulence increased, they reported this week in BMC informatics. They also identified an altered protein that helped block a molecular signaling pathway in human fetal neural stem cells—a possible mechanism that could help explain the virus-induced birth defects.
Source: BMC Informatics doi: 10.1186/s12966-017-0559-y