White Lion Cubs on display at Toronto Zoo

[platy]

It is not necessary to specifically breed for a recessive gene. The recessive gene won't be lost since there are still carriers in the wild population, naturally you just don't see as many of that particular phenotype. It's just leucism, there's not meant to be heaps of them and they're not meant to be the norm!
People are meddling in things that ought not be meddled.