Joining is free on Monday, May 12, from 10 a.m. until 2 p.m.

(SACRAMENTO, Calif.) -- Bone-marrow donation is proof that the kindness of strangers can save a life. Megan Livesey knows this firsthand.

"It was hard to believe that someone we didn't even know would be giving our daughter the most precious gift of all," she said. "One person can make an incredible difference."

Livesey's now 21-month-old daughter, Erica, was only 4 months old when she was diagnosed with infant ALL or acute lymphoblastic leukemia -- a cancer that affects the white blood cells needed to fight infections. After 10 months of intensive chemotherapy treatments, Erica relapsed. With no adequate match within their own family, the family began searching through the National Marrow Donor Program for a bone-marrow donor for Erica. One person was a good match.

"Even with millions of people in the bone-marrow registry, it is very difficult to find a perfect match." Megan said. "The truth is, we were just very lucky."

Bone-marrow transplants -- or stem-cell transplants -- can be the best treatment option for people with certain cancers, blood diseases and immune-deficiency disorders. The process involves destroying and replacing diseased bone marrow with new marrow that can produce healthy, normal blood cells.

Every new person added to the registry represents hope to the 6,000 people entered into the database each day in search of a donor. The need is especially great for donors who are Hispanic, black, Asian or biracial.

"We begin the unrelated donor search process as soon as we know that family members are not appropriate matches for a patient," said Kristine Ahlberg, bone-marrow transplant coordinator for UC Davis Cancer Center. "When a match doesn't happen right away, we have to wait for new registrants. It's one of the most difficult aspects of my job."

At UC Davis Cancer Center, 39 patients received stem-cell transplants in 2007. Six patients are still currently waiting for donors.

"Anyone could be that one person who can help," said Ahlberg, who has coordinated transplants for patients at UC Davis with donors from around the world. "I've seen it happen, and I'm always confident that it will again."

The Livesey family hopes to meet Erica's donor some day. They will make this request a year after the transplant, which is the recommended minimum waiting period. For now, all they know is that someone they do not know is saving Erica's life.

"We look forward to saying 'thanks' in person for what that donor has done for my daughter and our whole family," Livesey said.

UC Davis Cancer Center is among more than 80 cities around the country hosting a "Thanks, Mom!" bone-marrow registry drive on or around Mother's Day. The hope is that many people will honor the person who gave them life by doing so for someone else. The Sacramento event, hosted in collaboration with BloodSource, will be held on Monday, May 12, from 10 a.m. until 2 p.m. at UC Davis Cancer Center, 4501 X St., Sacramento.

Anyone ages 18 through 60 who is in good health and willing to donate to any patient in need can join the registry, which involves filling out a short health questionnaire and signing an informed consent form. A few cells are then collected by swiping the inside of the potential donor's cheek with a cotton swab. The cells are then used in tissue typing, information that is added to the registry and made available to National Marrow Donor Program Transplant centers nationwide. Joining the registry at the May 12 event is free.

The UC Davis Stem Cell and Bone Marrow Transplant Program performed the capital region's first bone-marrow transplant in 1993. Today, the program serves both adults and children and is the largest and most experienced of its kind in inland Northern California. It is the region's only National Marrow Donor Transplant Program site, giving UC Davis patients access to potential donors worldwide. For more information, visit www.ucdmc.ucdavis.edu/cancer/Specialties/BM T.html. For information about the "Thanks, Mom!" campaign, visit www.marrow.org/thanksmom. For information about health guidelines for donors, visit www.marrow.org