Two of the three biggest barriers to a return of the non-agency mortgage sector the premium capture cash reserve account and the qualified mortgage definition are embedded in the Dodd-Frank Act, industry officials say. And the third is whats not in the controversial law: any substantive reform of Fannie Mae and Freddie Mac. The biggest challenge to reducing the governments domination of the mortgage market is the lack of direction on the government-sponsored enterprises, said Tom Deutsch, executive director of the American Securitization Forum, during a hearing this week.