http://www.washingtonpost.com/wp-dyn/content/article/2007/05/27/AR2007052701056.html

If selflessness is doing something purely for someone else's sake,
and people are selfless because of a pleasurable feeling in the brain, similar to sex or food,
no one is truly selfless.

This article suggests that morality and immorality are genetically determined, would, then, it be right to excuse people for their transgressions, seeing as it was caused by a disease, or to kill them so that immoral genes die out?