In 2012, 6 miners in China got sick with a coronavirus and 3 of them died. They determined that the virus was able to travel from bats to humans, but not from human to human. The "bat lady" who is now the lead coronavirus researcher in the world works in the Wuhan Institute of Virology and she visited the mine where the 6 people became sick. She took samples from the mine and this is where RaTG13 (which is the closest coronavirus to Covid) was found.
Since the miners were able to get sick from the bats, but they did not pass the virus from human to human, this became the area of research. Can they do gain of function to make a coronavirus able to pass from human to human. There are published papers about adding the ACE2 receptor to a coronavirus (see research above).
Since the miners were able to get sick from the bats, but they did not pass the virus from human to human, this became the area of research. Can they do gain of function to make a coronavirus able to pass from human to human. There are published papers about adding the ACE2 receptor to a coronavirus (see research above).