More than 80 diseases and disorders can be treated with a stem-cell transplant, according to Canadian Blood Services, but only half of Canadians looking for a match will find one.

The odds are even more bleak for ethnically diverse Canadians, the agency says. With only 28 per cent of its stem cell registry being ethnically diverse, these patients will have a harder time finding a match.

This conundrum is covered in a new documentary called Mixed Match, which screened Tuesday night at the Reel Asian International Film Festival.

Advocate Athena Asklipiadis began working on the issue of bone marrow and stem cell matches for mixed-race patients years ago after her aunt died of lymphoma, a cancer of the blood. She approached film director Jeff Chiba Stearns about her work, and the idea for the film was born.

"With this kind of a film we want to bring attention to a topic that nobody really knows [about]," Chiba Stearns told CBC's Metro Morning on Wednesday.

"But also give hope that we can help save lives with this."

Asklipiadis explained that when looking for a bone marrow or stem cell match, the biggest factor is a patient's human leukocyte antigen (HLA) type. According to the National Marrow Donor Program in the United States, HLA is a marker, or protein, that is found on most cells in the body. Cells use that marker to identify other cells that belong in the body, and those that do not.

You inherit half of them from your father, and half from your mother. But about 70 per cent of Canadians who need stem cell transplants cannot find a suitable donor from within their own families, according to Canadian Blood Services.

'Impossible to match'

As Asklipiadis explained, patients need someone genetically similar to them in order to find a match for a stem cell or bone marrow donation.

"So for patients that are mixed race, there are just more variables involved, more chances that you're going to inherit a rare combination that you don't see very often," she said.

"Some patients have no trouble, but if you are mixed we do see that there is a trend that there are some that it's impossible to match."

Asklipiadis herself discovered that despite her mixed heritage, she inherited some common genetics. She has three possible matches in the United States and 26 worldwide, "which made me sad because I don't need a match and I have a lot."

'I'd be left with nobody'

Chiba Stearns, on the other hand, learned that of 25 million people on the international registry, he has one match.

"So if that person decided to drop out of the registry or decided they didn't want to go forward with a donation, I'd be left with nobody," he said.

While looking into the issue led to bad news for Chiba Stearns, he said the film and its message also offers hope because it will encourage people to join a bone marrow donor registry or donate cord blood and potentially help someone, somewhere cope with a health crisis.

For Asklipiadis, her call to action isn't just for ethnically diverse donors.

"There's tons of people searching. About 50,000 in North America are searching for matches and we can help find them," Asklipiadis said. "All of us have the ability to cure someone else in this world if they got sick. So we really encourage everybody to register."