DNA is irrelevant, and that's the entire point I'm trying to make. The selfish gene is a MYTH.
You and I are part of at least one social group -- these boards. If an outsider came into our group and started attacking you (flaming), I would be heavily inclined to jump to your defense despite almost certainly being completely unrelated to you.
If you and I were in a military unit, a neighborhood, an SCA group, a pinochle club, a Boy Scout troop, or a mutual admiration society -- or a country! -- together, the same rule would apply. Because humans -- and all other pack animals -- have a biological drive to defend members of their group even at their own expense. It just so happens that in civilized society, we do so by giving money to those less fortunate than we are, because we recognize that poverty kills.
Of course wolf packs cull other packs to keep their grounds -- just like human nations, political parties, and neighborhoods strike out against outsiders that they perceive as impinging upon them. That's normal. If the needs of the social group are dire enough, humans -- like bears and lions -- will turn on their own families and destroy their own kin (American Civil War). That's normal, too.
The social group is the important factor here, and it always was.
Is that a moral imperative? Define 'moral'.