zlacker

"Gain of function research" is when you stimulate micro-organisms so that they gain new attributes. For viruses these properties could be infectiousness or antibody resistance.

One way you can do that is by putting evolutive selection pressure on the micro-organisms. For instance, submit a colony of bacteria to something they are vulnerable to. Stop when 90% of the colony is dead. Cultivate the colony back to a full size, then repeat the protocol until you get bacteria that are fully resistant.