Until earlier this year, Shyanna Anzivino, 7, was a shy girl who enjoyed swimming and roller skating.

Shyanna has overcome that shyness in recent months, according to her parents, but for reasons that no family would wish on a child. After she complained that she wasn’t feeling well, she was diagnosed with a rare, potentially fatal disease, aplastic anemia, in which the body stops producing new blood cells.

It can result in fatigue and a heightened risk of infection and bleeding — dangers that will prevent Shyanna from skating or swimming anytime soon. Along the way, she has been subjected to tests, blood transfusions and hospital visits.

Before all that, Shyanna “was probably the shyest kid you’d ever meet,” said her father, Richard Anzivino. “But now, she’ll walk right up to you. She knows ‘no’ isn’t an option. She’s a totally different person.”

As Shyanna prepares for an extensive treatment in Boston later this month, her father and mother, Patience Anzivino, also aren’t being shy.

Their daughter will receive a bone marrow transplant, and they’re urging other Mainers to become registered bone marrow donors by participating in a registry drive and fundraiser that’s being held Friday evening at Winthrop Grade School.

The fundraiser, which runs from 5:30 p.m. to 7:30 p.m., is to help the Anzivino family cover expenses related to Shyanna’s treatment.

The registry drive, which is free and open to people 18 to 44 years old, is meant to expand the overall pool of patients who could benefit from a bone marrow transplant. Participants are required to bring their health insurance cards.

Shyanna was particularly lucky to match with a donor because both her parents have a mix of American Indian and European heritage.

Bone marrow types are tied to ethnicity, and people from mixed backgrounds are underrepresented in the overall registry. Only 2 percent of Americans are on the registry, and of those, multi-racial people have the worst odds of matching with a donor, according to statistics compiled by the Institute for Justice, a public interest law firm.

“There is just not enough people in there to match everybody,” said Richard Anzivido, who works as an educational technician at Winthrop Grade School. “People who say they don’t have a match, I don’t want for anybody else to be in that position. We’re hoping that by doing this, that a match comes out of this for somebody else.”

Bone marrow transplants are used to treat several different diseases that affect the blood stream, including cancers such as leukemia and lymphoma, according to the organization that runs the national registry, Be the Match. In combination with chemotherapy and radiation, they are meant to replace diseased blood cells and marrow, and get healthy cells circulating through the body. More than 14,000 patients are in need of transplants.

The technology for transplanting bone marrow and registering as a donor has changed considerably over the years, said Rachel Miville, the school nurse in the Winthrop School Department, who is helping to organize the drive on Friday.

People might think of large needles when they imagine the process of registering as a donor, but it’s far gentler than that, according to Miville.

“It’s a very painless process,” she said. “You go to a site, they swab your cheek and you wait; and if you’re called upon, if I were doing it, I would consider it an honor to be able to save someone.”

To join the registry, people must be 18 to 60. If would-be donors are older than 44, they must pay a $100 fee. The Winthrop registration drive will not be open to people older than 44.

One in 430 people on the U.S. registry will go on to donate, according to Be the Match.

The organization does not appear to carry state level data about the demand for transplants among Maine patients on its website, and a state recruiter for the program did not respond immediately to a request for information on Wednesday.

But Miville noted that there are several other Winthrop area residents who have health problems that will require bone marrow donations and for whom the community will be holding similar fundraisers in the coming months.

One of them is Zach Nadeau, a 2013 graduate of the Winthrop school system, who has leukemia and is looking for a bone marrow match. Another, the mother of two students, has been diagnosed with breast cancer.

“I’ve always been a strong believer in making a difference where you are,” Miville said. “It can be hard to think, ‘How can I help make a difference?’ If you look at your immediate surroundings and look around, if you start there, it’s an important concept for people to embrace.”

Questions about participating in the Winthrop drive or joining the bone marrow registry can be directed to the Maine recruiter for Be the Match, Paul Greenier, at 242-3529.

Charles Eichacker — 621-5642

[email protected]

Twitter: @ceichacker