SINGAPORE - What is perhaps more disappointing than not finding a matched unrelated donor is finding someone who has a change of heart and says "no".
About half of the local donors drop out this way.
The reasons range from fear of pain to lack of time and family objections, said Ms Lim Lay Feng, a search coordinator at the Bone Marrow Donor Programme (BMDP), which operates and manages Singapore's only database of volunteer donors.
To be listed, donors just have to have a cheek swab, which is then tested for the human leukocyte antigen markers that are found in almost every cell of the body and used to identify a matching donor for a patient.
When a suitable donor among brothers and sisters cannot be found, transplant centres will send a search request to the BMDP.
If no match can be identified locally, the BMDP will automatically extend the search around the world through a consolidated global database of volunteer donors.
BMDP president Jane Prior said it is important to know that patients and their families do not need to contact friends in other countries to try and initiate a donor search.
Last year, the BMDP received 510 search requests here and overseas, more than the 314 received in 2008.
The odds of being a match for a patient in the same racial group is around one in 20,000, so a large pool of volunteer donors is needed to increase a patient's chance of finding a match.
BMDP is now on an aggressive drive to expand the number of potential donors on the register here, which stands at 55,000 now, to about 75,000 people by 2015.
Last year alone, slightly more than 5,000 donors were recruited, more than twice the number recruited in 2011.
Its Match For Life donor recruitment campaign was launched last October and showcased real donors as being feisty and vibrant.
What it has not done is to appeal to the public through pictures of patients waiting for a transplant, an approach which has been used in the United States and Britain, MsPrior said.
She explained: "We don't want people to sign up for that emotional kick of helping a cute child. We want them to donate to anybody."
Ms Prior said students tend to be most open to the idea of donating bone marrow stem cells through roadshows held in polytechnics and universities, compared with the rest of the population who have not warmed up to doing this for non-family members.
BMDP wants to recruit people aged 18 to 49, though donors can remain on the register up to the age of 60.
To register as a potential bone marrow donor, collect a swab kit from the Bone Marrow Donor Programme (46South Bridge Road, 03-02 Kingly Building), National University Hospital (Blood Donation Centre, Main Building1, Level 1) or Singapore General Hospital (Haematology Centre, Block 7, Level 2).
You can also fill in your details at www.bmdp.org/uCanhelp_donor_signup.html to have a kit sent to you.
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