Genes are not simple triggers. No one is hardwired to commit murder or any other crime. Our actions are always the result of stupendously complex gene-environment interactions, and environment is likely to remain the more important influence by far.
“Who ever hears of fat men heading a riot, or herding together in turbulent mobs? No - no, your lean, hungry men who are continually worrying society, and setting the whole community by the ears.”
“A man must dream a long time in order to act with grandeur, and dreaming is nursed in darkness.”