Actually you just need a few females, and a large store of sperm to provide genetic diversity in further generations. If you used inseminated eggs (so the mothe

Actually you just need a few females, and a large store of sperm to provide genetic diversity in further generations. If you used inseminated eggs (so the mother has no genetic relation) you can bring the human race to another planet with only a few people. When you get to the habitable planet, you let the population grow. Also since a large genetic pool comes with the colonists, it limits genetic drift.