And what "like snow" skin is ancestrally passed along?

You might want to consider also Lamentations 4:7 as well before dismissing the notion of an endogamous subpopulation with ancestral pale/ruddy skin.

Or 4Q534 from the Dead Sea scrolls claiming Noah had red hair.

Also, the leprosy descriptions seem like they may have been skin cancer:

https://www.thetorah.com/article/tzaraat-as-cancer