Southern Europeans, non-Europeans less likely to have matched stem cell donors

March 27, 2019

(WASHINGTON, March 27, 2019) -- Although the pool of registered bone marrow donors has increased in recent years, a new study suggests that most people of southern-European and non-European descent are unlikely to have a suitable match if they need a life-saving bone marrow transplant.

If an immediate registry search does not identify a donor, alternative transplant strategies should be considered according to Juliet Barker, MBBS, Director of the Cord Blood Transplant Program at Memorial Sloan Kettering Cancer Center in New York City, author of a study published online today in Blood Advances, a Journal of the American Society of Hematology (ASH).

A bone marrow transplant is a potentially life-saving procedure in which the patient's cells are replaced with healthy new ones. The ideal donor is usually a brother or sister with the same genetic markers as the recipient. However, for those who do not have a suitable sibling, transplant from a matched unrelated volunteer donor is usually considered the next best option.

At the Memorial Sloan Kettering Cancer Center's Adult Bone Marrow Service, a large and ethnically diverse transplant program where this study was conducted, approximately 75 percent of patients do not have a sibling match.

Dr. Barker and her team followed 1,312 patients who needed a bone marrow transplant for treatment of life-threatening blood cancers and who initiated donor searches from 2005-2017. All patients shared their family history as far back as known, including where they were born, what they considered their race and ethnicity to be, and where their parents and grandparents were born. Researchers categorized the patients into groups in terms of their racial and ethnic origins and tracked if they could go to transplant with a matched adult donor, or whether they required a mismatched adult donor or a transplant using neonatal cord blood cells.

Dr. Barker and colleagues report that people of European descent were more likely to receive a transplant from an unrelated fully matched donor than were non-Europeans. Of the total Europeans in the study, 67 percent received a matched transplant compared to 33 percent of non-Europeans (including Asians, White Hispanics, and Africans).

Compared to people from other parts of Europe, the majority of Southern Europeans were unlikely to have a fully matched donor (41% Southern Europeans v. 64-77% for other European patients). Southern Europeans' rate of receiving a match was closer to the rates observed with Asians and White Hispanics. Individuals of African descent were least likely to undergo transplantation from a fully matched donor.

"We have identified tremendous racial and ethnic disparity in transplant access," said Dr. Barker. "What's more, it has been thought by some that if you just increase the number of registered adult donors that it would resolve this problem, but it hasn't. This study provides a clear demonstration of how important it is to fund initiatives that will improve outcomes of alternative donor transplantation including the use of unrelated donor cord blood."

"It has been previously recognized that non-European patients have difficulties finding a match. But we have also found that those originating from the south of Europe can also be difficult to match. This hasn't always been widely appreciated," said Dr. Barker. "It is also important to fully understand the patient's ancestry as it cannot be assumed that a patient who is predominantly European, but may have part non-European origins, is going to have a match."

The majority of those who did not have a full match either received partial match (17% of all patients) or cord blood transplant (24%). Of all patients, 4 percent did not receive any type of transplant. The majority of these individuals were of African descent.

"Transplant centers now have the technology to search adult donor registries and immediately estimate the chance their patient will have a matched donor," said Dr. Barker. "If the search is poor, centers should immediately pursue alternative donors. Futile adult donor searches and donor drives should be abandoned. This is more and more important as our population increasingly becomes more diverse."
-end-
Blood Advances is a peer-reviewed, online only, open access journal of the American Society of Hematology (ASH) (http://www.hematology.org), the world's largest professional society concerned with the causes and treatment of blood disorders

ASH's mission is to further the understanding, diagnosis, treatment, and prevention of disorders affecting blood, bone marrow, and the immunologic, hemostatic, and vascular systems by promoting research, clinical care, education, training, and advocacy in hematology.

Blood Advances® is a registered trademark of the American Society of Hematology


American Society of Hematology

Related Bone Marrow Transplant Articles from Brightsurf:

Nanoparticles can turn off genes in bone marrow cells
Using specialized nanoparticles, MIT engineers have developed a way to turn off specific genes in cells of the bone marrow, which play an important role in producing blood cells.

How stress affects bone marrow
Researchers from Tokyo Medical and Dental University (TMDU) identified the protein CD86 as a novel marker of infection- and inflammation-induced hematopoietic responses.

Big gains in bone marrow transplant survival since mid-2000s
A bone marrow transplant can be a lifesaving treatment, but it can come with life-threatening risks.

Dangerous bone marrow, organ transplant complication explained
Scientists have discovered the molecular mechanism behind how the common cytomegalovirus can wreak havoc on bone marrow and organ transplant patients, according to a paper published in the journal Cell & Host Microbe.

Viagra shows promise for use in bone marrow transplants
Researchers at UC Santa Cruz have demonstrated a new, rapid method to obtain donor stem cells for bone marrow transplants using a combination of Viagra and a second drug called Plerixafor.

Bone marrow may be the missing piece of the fertility puzzle
A woman's bone marrow may determine her ability to start and sustain a pregnancy, report Yale researchers in PLOS Biology.

Uncovering secrets of bone marrow cells and how they differentiate
Researchers mapped distinct bone marrow niche populations and their differentiation paths for the bone marrow factory that starts from mesenchymal stromal cells and ends with three types of cells -- fat cells, bone-making cells and cartilage-making cells.

Can human breast milk reduce intestinal injury following bone marrow transplant?
A new pilot study compared the use of human breast milk to formula in children less than five years of age who underwent bone marrow transplant, measuring the levels of inflammatory and pro-inflammatory biomarkers in the stool and blood to assess inflammatory injury to the intestinal microbiome.

New material will allow abandoning bone marrow transplantation
Scientists from the National University of Science and Technology 'MISIS' developed nanomaterial, which will be able to restore the internal structure of bones damaged due to osteoporosis and osteomyelitis.

Blood diseases cured with bone marrow transplant
Doubling the low amount of total body radiation delivered to patients undergoing bone marrow transplants with donor cells that are only 'half-matched' increased the rate of engraftment from only about 50 percent to nearly 100 percent, according to a new study by Johns Hopkins researchers.

Read More: Bone Marrow Transplant News and Bone Marrow Transplant Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.