I also find the female DNA found within the bomb contents irrelevant as well. Tamerlan Tsarnaev would have the DNA of his SPOUSE on his person. It doesn't mean anything. I am assuming they had sex at one time or another.
The Tsarnaev brothers were self radicalized. What else does anyone need to know? The agencies have to disseminate information better to the local level where a better understanding can be discerned.
This is an American problem and until it is solved within the abilities of the USA to solve it domestically it won't go away.
What are we doing TODAY to be sure local communities have better information to protect citizens NOW!