Transcript for Man, 18, says he was abused by disgraced USA Gymnastics doctor
troubling new development in gymnastics tonight. The first male gymnast accusing former team doctor Larry Nassar of sexual abuse. Jacob Moore breaking his silence. What he says the doctor did to him. Here's ABC's kayna Whitworth tonight. Reporter: Jacob Moore is a standout gymnast at the university of Michigan, and is now coming forward as the first male victim with allegations against disgraced doctor Larry Nassar. I don't think it was by any means a stupid kid, but I don't know anything about medicine, so, you know, I kind of placed a lot of trust in him. Reporter: Jacob says at just 16, he was abused in the basement of Nassar's home while seeking treatment for a shoulder injury. Jacob claiming in a federal lawsuit that "Nassar administered act cue puncture to Moore's pubic area, ostensibly for the purpose of treating his shoulder pain." I felt uncomfortable, but the amount of trust I had in him led me away from thinking that something was actually wrong with the situation. Reporter: The 18-year-old says he only recently came to terms with what happened. I started searching the internet for evidence that this was a legitimate medical treatment and I didn't find anything. And I immediately was very shocked and almost angry, you know, I was abused, basically. Reporter: His sister kamerin says she, too, was abused by Nassar, someone they considered a family friend. One of more than 200 victims speaking out at sentencing, describing her brother's alleged assault. You pulled down his pants slightly down to expose him in front of one of your other female victims, actually. Reporter: Jacob says he was inspired by his sister and hopes to one day testify against Nassar in a civil car. He's a survivor, and he's there to speak for those who have come forward. Reporter: For now, Jacob is focused on moving forward. If I allow him to kind of take away that love for the sport, I see that as kind of him winning. That's the last thing that, you know, any of us want. And kayna Whitworth here with us in New York tonight. And Jacob is now joining a lawsuit with other victims? Reporter: David, he is joining more than 250 victims in a lawsuit against Nassar, usa gymnastics, Michigan state university and others, as well. And Jacob told us that by speaking out, he hopes that he can give other male victims a comfortable platform so that they can have their voulss heard, as well. A troubling new development. Fleiss nice to have you here in new York.
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