The New York Times, January 18, 2021 (with Jonathan Corum)
At the heart of each coronavirus is its genome, a twisted strand of nearly 30,000 “letters” of RNA. These genetic instructions force infected human cells to assemble up to 29 kinds of proteins that help the coronavirus multiply and spread.
As viruses replicate, small copying errors known as mutations naturally arise in their genomes. A lineage of coronaviruses will typically accumulate one or two random mutations each month.