Social media has become crucial for news and current events, but it’s also becoming a place for medical miracles.

Lara Casalotti hopes one of those miracles has her name on it.

The 24-year-old woman is currently undergoing treatment at London’s University College Hospital after being diagnosed a week before Christmas with acute myeloid leukemia.

Casalotti needs stem cells, but what makes her case unusual is that she is of mixed race heritage: Thai, Chinese, and Italian, to be precise.

Stem cell matches work best when the donor and recipient are the same ethnic mix. But only 0.5 percent of registered donors have East Asian backgrounds, according to Anthony Nolan, a leading bone marrow charity based in London.

Since there are so few donors for ethnic minorities, patients of Asian, black, and other minority ethnic backgrounds have less than a 20 per cent chance of finding a suitable match.

When it was determined that Casalotti’s brother was not a match, the family launched Match4Lara.com, an appeal not only for Casalotti but also to raise awareness for other blood cancer patients from ethnic minorities. Among other things, the website lists local places where readers can register as potential donors.

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Committed Young Woman

At the center of all the outreach is a young woman with a serious commitment to humanitarian causes.

When she got sick, Casalotti was working in Thailand to improve conditions for migrant workers. Previously she worked with the United Nations and Human Rights Watch.

“Lara is staying positive,” Charlotte Sagan, her cousin and family spokesperson, told Healthline. “We have to limit the number of friends she can see each day … too many visitors increases the risk that someone brings in an infection.

Last I talked to her, she said she was craving sushi, which she is currently not allowed to have.”

Casalotti herself posts updates on her blog in which she thanks people for registering. She recently wrote, “I have to go into the hospital every day to receive 2 of my 3 chemotherapy drugs, whereas this third chemo drug is attached to me at all times and kept right by my side. I've named it Bob.”

Sagan said it’s been quite an experience to see her cousin’s health circumstances become a worldwide cause.

“She is happy that she is part of a cause that will help other patients as well,” she said. “What started as our family around a table has turned into a huge viral campaign. It was very organic and fueled by people who have seen our cause, joined the registry, and spread the word.”

In fact, as word has spread, some noted names have tweeted their support as well:

  • English comedian Stephen Fry wrote, “Mixed race? You can do something with your unique identity — save a life.”
  • J.K. Rowling, the author of the Harry Potter books, also urged people to register: “A Eurasian donor is desperately needed to save this young woman’s life. Do your thing, Twitter!”

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Donor Shortage a Worldwide Problem

The Asian American Donor Program (AADP), based in Alameda, California, has worked to raise awareness about stem cell donation for 26 years.

Carol Gillespie, the executive director, has a front-row seat on the shortage of minority and mixed-race donors. AADP is an official recruitment center of the Be The Match organization.

“This is a bigger issue than one woman, but this family … they’re educated and well connected throughout the world,” Gillespie said in an interview with Healthline. “They have a big family in London and in Thailand, and the U.S. And because Lara is socially conscious, they wanted that image portrayed.”

“We can do a worldwide search for a donor,” she said. “We share registries all over the world.”

That’s important because finding a marrow/stem cell match can be like finding a needle in a haystack.

“Multi-racial patients face the worst odds,” Gillespie said in a press release. “We need every one of mixed race ancestry to step forward and join the registry.”

Read More: People With High Blood Pressure, Diabetes Advised Not to Donate Kidneys »

Registering Is Simple

Registering to become a potential donor consists of spitting into a test tube or swabbing your cheek. That’s all.

Human leukocyte antigen (HLA) typing is used to match bone marrow donors and recipients. HLA is a protein — or marker — found on most cells. The immune system uses HLA markers to know which cells belong in the body and which do not.

If the recipient’s body accepts the donated stem cells, they start to make healthy blood cells again.

In nine out of 10 cases, making a stem cell donation is simple, similar to giving blood (although blood type is irrelevant in making matches)

A perfect match is 10 out of 10 antigens.

“That’s very difficult” to find, Gillespie said. “[Casalotti’s] best shot might be eight out of 10.”

That could likely leave Casalotti with graft vs. host disease, a risk that can occur with stem cell donation. Essentially the donor’s immune cells attack the patient’s normal cells. That disease, while treatable, is why the search for a perfect stem cell match goes on.

“Every person who joins counts,” Sagan said.