LOS ANGELES — Omar Akersim prays regularly and observes the dawn-to-dusk Ramadan fast. He is also openly gay.Akersim, 26, is part of a small but growing number of American Muslims challenging the long-standing interpretations of Islam that defined their parents’ world. They believe that one can be gay and Muslim, that the sexes can pray shoulder-to-shoulder, that females can preach and that Muslim women can marry outside the faith — and they quote the Quran to back them up.The shift comes as young American Muslims reshape the faith they grew up with to fit their complex, dual identity, with one foot in the world of their parents’ immigrant beliefs and one foot in the ever-shifting culture of America. The result has been a growing internal dialogue about what it means to be Muslim, as well as a scholarly effort to re-examine the Quran for new interpretations that challenge rules that had seemed set in stone.“Islam in America is being forced to kind of change and to reevaluate its positions on things like homosexuality because of how we’re moving forward culturally as a nation. It’s striving to make itself seen and known in the cultural fabric and to do that, it does have to evolve,” said Akersim, who leads a Los Angeles-based support group for gay Muslims. “Ten or 15 years ago, this would have been impossible.”The shift doesn’t end with breaking obvious taboos, either. Young American Muslims are making forays into fashion and music (Islamic punk rock, anyone?), and stirring things up with unorthodox takes on staples of American pop culture. A recent controversial YouTube video, for example, shows Muslim hipsters — or “Mipsterz” — skateboarding in head scarves and skinny jeans as Jay-Z’s “Somewhere in America” blasts in the background.Nearly 40 percent of the estimated 2.75 million Muslims in the U.S. are American-born and the number is growing, with the Muslim population skewing younger than the U.S. population at large, according to a 2011 Pew Research Center survey.