CNN The Situation Room May 2, 2013 22:41:00
Similarities for example, between these serial killers and people who commit terrorism, and seeing if there are some commonalities there. it's not ironclad by any means, it's an emerging science, but he's the guy sort of trying to investigate this. >> what about the role of genetics? the two tsarnaev brothers obviously related. is there a connection in violence and genetics? >> when you look at researchers how much is biology and how much is environmental, you get back the answer often, it's about 50/50. you know there's 50% maybe related to genetics. and when you talk about brothers like this...
Source: archive.org