Multiracial patients face donor problems

Multiracial patients often have a hard time finding bone marrow donors:

Luke Do was a lively 18-month-old awaiting the birth of his first sibling when he was diagnosed with a rare form of leukemia.

The hopes of his parents, both doctors in San Jose, Calif., immediately turned to a bone marrow transplant, but they soon learned some distressing news — Luke's ethnic heritage made him a tough match.

Sarah Gaskins, Luke's mother, has Japanese and European ancestors and his father, Lam Do, is Vietnamese-American. Because bone marrow matches usually are made with a relative or someone with the same racial or ethnic background as the patient, multiracial people rarely have success.

"It's tragic," said Lam Do, who specializes in internal medicine. "Your chance of finding a donor is so low, it's like winning the lottery. And most people are unaware of this."

For years, the medical community has pushed for increased donor registry among racial minorities to improve survival rates for leukemia, lymphoma and other blood diseases. But to the general public, the situation is little known.

Only 2% of those who list their ancestry with the National Marrow Donor Program are multiracial, though the NMDP will — for the first time — study multiracial patients' medical records this year to better understand what kind of marrow tissue they tend to inherit from their parents. The group also will try to more effectively recruit new potential donors, said Helen Ng, an NMDP spokeswoman.

"Using the patient information we have access to, we're trying to understand a little better the issues they face," said Ng, whose group, with 5.6 million potential donors registered, has the largest such list in the world.

Matt Kelley, president of Mavin Foundation, a Seattle-based advocacy group for multiracial people, says the inattention to the problem reflects society's reluctance to accept today's increasingly complex racial landscape.

"It's a headache," said Kelley, whose group has an ongoing bone marrow program. "The reality is that many organizations are afraid of addressing race period — they don't feel competent or comfortable — and when it comes to addressing mixed heritage issues, they don't want to go there, either."

Today, whites in need of a bone marrow transplant have about a 90% chance of finding a match, said Dr. Patrick Beatty, an oncologist with the Montana Cancer Specialists in Missoula, Mont., who researches ancestry and bone marrow. For those who aren't white, "your chances of getting a match are pretty remote," he said.

The biological reason has to do with the body's response to infections, Beatty said. Because the world's ancient peoples were exposed to different diseases over millennia, each group developed different tissue antigens, substances that help fight illness.

The descendants of these peoples retain those highly varied tissue antigens, he said, making it tough to match the bone marrow of individuals from different ancestries.

Much of today's "racist" objections to intermarriage probably have to do with an innate desire to maintain the tissue antigens acquired by our ancestors over the centuries.