A new genetic sequencing study reveals SARS-CoV-2, the virus responsible for coronavirus, originated from a single source in Wuhan, China. However, many of the localized cases in the US show Europe as the most likely source of infection. The study also identified a SARS-CoV-2 mutation that has never been seen before, where 81 of the letters have been permanently deleted from the genome. The mutation mirrors a large deletion that occurred during the 2003 SARS outbreak. During the mid-to-late phases of the 2003 SARS infection, the accumulated mutations attenuated the virus, leaving a weakened form of infection that resulted in less severe symptoms.