So, I assume that if you put 100 people on a spaceship and sent them to wherever, they’d get very inbred in a few generations. How many people would you need for this to not happen, accounting for the fact that there will eventually be people who are infertile or die before having children?
It seems very plausible that if you can make a generation ship, you could make something like CRISPR to artificially increase genetic diversity/eliminate potential birth defects. Or perhaps just store genetic material for more people than the actual colonists on the ship. You’d probably want to hedge your bets in case there’s a low survival rate. There’s a lot that could go wrong. Ecosystem failure, negative effects of radiation, or just good old fashioned murder.