Keone Penn’s middle initial — D — actually stood for Denard, but it could have easily been short for determination.

When Penn was 12 years old, he was thrust into the medical spotlight as the first person in the world to undergo a groundbreaking stem cell transplant that ultimately cured him of sickle cell disease. It was a painful process but he was determined to beat the disease and the health complications that would follow, his mother, Leslie Brodnex said.

Not long before his 27th birthday, an age his doctors never imagined he’d reach, Penn did something else they said he’d never do: He enrolled in culinary arts school.

“He was determined to prove those doctors wrong,” said his sister, Seterria Brodnex, of Atlanta. “He was so excited, and nothing was going to stop him from doing what he wanted to do.”

But on June 10, the night of his 27th birthday, something terrible happened, his mother said. She found him in his bedroom, the victim of an apparent assault that put him in the hospital. Gwinnett Police are investigating, according to an incident report.

Penn, of Gwinnett County, died June 20 at Gwinnett Medical Center from complications of sepsis, his mother said.

A funeral is planned for 11 a.m., Friday at Solid Ground Christian Ministries, Lithonia. Burial at Hillandale Memorial Gardens will follow the service. Gregory B. Levett & Sons Funeral Home, Gwinnett Chapel, is in charge of arrangements.

Penn’s mother found out her son had sickle cell disease when he was 6 months old and they lived in North Carolina. After more than seven years of trips to and from Duke University’s hospital from their home in Fayetteville, N.C., Leslie Brodnex packed up her son and moved to Atlanta because she heard medical centers were conducting sickle cell studies.

“I thought back then if I could just get to Atlanta, then maybe Keone could get involved with a research project,” she told a reporter from The Atlanta Journal-Constitution in 2000. “But once we were here, the funny thing was that they came to us about the stem cell transplant.”

On Dec. 11, 1998, in a six-hour operation at Children’s Healthcare of Atlanta at Egleston, Penn received an umbilical cord blood transplant from an unrelated donor. Thirty-six days later, tests showed no evidence of the sickled cells growing back in his blood. Within three years, he was taken off the steroids he’d been prescribed and the swelling in his joints, which had severely hampered his mobility, subsided.

Penn traveled to Washington in 2003 and 2005 to tell his story to politicians debating stem cell research. He also told his story to Georgia legislators, and has his name on Georgia Senate Bill 148, known as “Keone’s Law,” which “personifies his life’s purpose and commitment to mankind,” his family wrote in his obituary. The 2007 law established a 15-member state commission that would oversee a system of umbilical cord blood banks and seek grants for non-embryonic stem cell research.

In 2007 Penn told an AJC reporter the proudest moment in his life, at that point, was his 2004 graduation from Shiloh High School. That accomplishment was eclipsed recently by his acceptance at The Art Institute of Atlanta, his mother and sister said.

“He made honor roll two quarters in a row,” his sister said. “He was so excited about the learning process and getting more [cooking] knowledge.”

Penn’s love for cooking stemmed from his love of scrambled eggs, his sister said. When he was younger his favorite food, no matter the time of day, was scrambled eggs.

“We got tired of always cooking him scrambled eggs and we told him we were going to teach him how to do it,” she said. “And it just took off from there.”

Even when Penn didn’t have an appetite, or couldn’t eat solid food, he still wanted to prepare meals for others, his mother said.

Though the stem cell transplant cured him of the sickle cell disease, it left him with a host of other complications, including diabetes, she said. But he was determined to soldier on, no matter what.

“One day his blood sugar was low and he had to get treatment, all he could think about was going to school,” Brodnex said. “As soon as it returned to normal and he’d rested up, he was out the door. He was finally living his dream.”

In addition to his mother and sister, Penn is survived by a number of relatives and friends.