As an actor, Ernest Emmanuel Peeples has portrayed a real range of characters — from Hamlet to the Ghost of Christmas Present. But in recent months, one particular theatrical role stands out from the rest: the opportunity to portray Lu, one of the adolescents at the center of Jason Reynolds’ wildly popular young adult novels, one of which is now also a play. Like Peeples, the character Lu has albinism, a genetic condition involving a lack of pigment that affects one’s skin, hair and eyes. Having this in common with a character is a first for Peeples, and a meaningful one. In this episode of St. Louis on the Air, he talks with host Sarah Fenske about his role in Metro Theater Company’s “Ghost,” which runs now through March 1 at the Grandel Theatre. The production is directed by Jacqueline Thompson, who also participates in the discussion.