Washington (CNN) -- Letting openly gay or lesbian troops serve in the military would have little lasting impact on the U.S. armed forces, a major Pentagon review has found, several sources familiar with the results told CNN Tuesday.
Putting an end to "don't ask, don't tell" would have "some limited and isolated disruption to unit cohesion and retention," the year-long study found, but the effects would not be long-lasting or widespread.
There will be some strong minority opposition, particularly in the Marines and some combat arms specialist units, said the chairs of the study, Defense Department General Counsel Jeh C. Johnson and Army Gen. Carter F. Ham.
As many as 40 to 60 percent of troops in those units were against changing the 17-year-old policy that lets gay and lesbian troops serve as long as their sexual orientation is secret.
Overall opposition throughout the military was about 30 percent -- roughly the same as it is in America as a whole, according to recent findings from CNN/Opinion Research Corp. and the Pew Forum.