Eric Dane, star of "Grey's Anatomy," opens up about his ALS diagnosis in an upcoming interview.

Actor Eric Dane, known for his role as Dr. Mark Sloan on "Grey's Anatomy," discussed his ALS diagnosis in an emotional interview with Diane Sawyer on "Good Morning America." Dane expressed hope that this is not the end of his story, showing determination not to let the disease define him. The full interview will air on June 16 at 7 a.m. ET.