At 21 years old, McKinley has had hundreds of blood transfusions to treat severe pain as a result of sickle cell disease. He’s one of more than 100,000 people in the U.S. affected by the disease, most of whom are of African, Latino and Mediterranean descent. Sickle cell disease distorts round, healthy red blood cells into crescent-shaped ones, making it difficult for them to flow through the bloodstream and carry oxygen to the body. When these red blood cells get stuck in the blood vessels and block blood flow throughout the body, the result is a pain crisis. “For so long, no one knew of his condition,” said Angelica, McKinley’s mother. “People in McKinley’s circle only knew that at times his skin looked discolored, his eyes were yellow, he was out of school for a month then he would return, and he looked fine. For all these years, it’s been the hundreds of blood transfusions that got him through the worst of times, gave him relief, and allowed him to return to living his life.” Las...