Scientists tracking mutations of the new coronavirus say there is no evidence its changes have made the virus deadlier or more contagious.

But they are tracking the virus’s genetic changes, which are common and typically benign, to better understand how it is being transmitted around the world and help combat its spread.

The novel coronavirus, or Sars-CoV-2, and all other coronaviruses are made up of RNA, which has a slightly different chemical makeup than DNA. Viruses with an RNA genetic code also mutate easily. When the virus makes a copy of itself, it often makes mistakes and changes a small piece of its genome, which helps it adapt to its environment.

“It’s a natural process of a virus being a virus,” said Nathan Grubaugh, an assistant professor of epidemiology of microbial diseases at the Yale School of Public Health.

But those changes aren’t innately dangerous. Virologists say most mutations are “silent,” meaning they don’t change any of the virus’s behaviors.