Hybrids

With the introduction of alien races some want to have offspring, naturally few races can facilitate this, but with science this is a simple fix with gene editing that can create hybrid child, the chances of the child being able to find a compatible mate lessens and they will have to continue to use the gene editing process if they want a direct lineage.

Certain groups are against this practice, race purist, anti editors etc but as long as there is love people will try it.