Comment Why they want to do this: (Score 1) 16
Lets say you are trying to save a near-extinct species. Say for example the Capitalist Republicanus. (These are pretty rare, because the current Republicanus King hates capitalism. He is a Mercantilist that likes tariffs, something Adam Smith hated so much, he created Capitalism.)
So there are only 150 C.Republicanus left, where there used to be millions of them. And of course, most of them are related to each other, as they all live in small communities. This has significantly reduced genetic diversity of the C. Republicanus. Many of them are susceptible to the same disease (Neverus Impeachus).
{Ending joke, real science to follow}
But lucky you, in museums there are several different taxidermy examples of the original specie left. They are old and not properly preserved, but it is possible to examine the skin cells of those stuffed animals. You can't get enough to clone them, but you CAN get about 30% of genetic code. Which you can compare to the living species.
Then you look for the genetic variants and see about 40-100 genes that used to exist in the species before the genetic bottle. You can create 50 different viri that inserts these old genes into the current species. You expose 50 different members of the current species, adding most of those old genes into the current members.
You are not cloning or creating new species, you are re-introducing real genetic diversity that used to exist but is no longer found.
This can make the species far more resilient and make the incestuous nature of the remaining species far less dangerous.
This is what the scientists want to do. They are adding diversity and preventing the problems of all the members currently being related to each other. It means one virus is less likely to kill the entire remaining species, and may fix other problems that come from inbreeding (see pure bred show dogs for the many, many problems that inbreeding causes).