KEY POINTS:
Rachel Sharma has spent nearly half her life battling illness.
The 20-year-old Aucklander wants to be a counsellor or social worker and now - thanks to the bone marrow donor registry - she will soon be able to pursue her dreams.
The Mt Wellington resident was diagnosed with acute lymphoblastic leukaemia in 1999. She underwent chemotherapy, and attained complete remission.
But in May 2006 she developed myelodysplastic syndrome, another serious blood disorder.
Despite treatment, she still needed a bone marrow transplant, but her two older sisters were not a match.
An international search by the New Zealand bone marrow donor registry failed to find a match - a problem not uncommon with non-Europeans.
Registry co-ordinator Raewyn Fisher says that although there are 11.6 million donors on registries around the world, the vast majority are European.
For this reason, the New Zealand register managed by the Leukaemia & Blood Foundation is not recruiting Pakeha donors. It is instead concentrating on Maori, Pacific Islanders and other ethnic minorities such as Indians.
Ms Fisher says the recruiting drive for Maori and Pacific Island donors which started in 1996 means that matches are now found for about 80 per cent of Maori and Pacific patients.
But New Zealand's changing demographic means other ethnic groups are now facing the same problems that previously confronted Maori and Pacific Island patients.
Ms Fisher says the chance of finding a matching donor is very low for the Indian group, which includes people from India, Pakistan, Sri Lanka and Fiji Indians, as there is no established registry in India.
Tissue types are inherited, so patients are most likely to find a donor from within their own ethnic group. Intermarriages can make for a more complicated search.
"It's hard enough, for example, finding a person of Indian extraction, but if you're then going to mix that with Polynesian, for example, then you're going to have quite a problem."
If donors are unavailable, an alternative is cord blood, which does not need to be a complete match. Until recently, it was available only for children because of the limited number of cells.
"If none of those match, and sometimes that is the case, then the hope is on chemotherapy - that they can have some sort of life."
But in the past two years, medical advances have allowed for the use of two cord blood units to make up the number of cells required for an adult.
Two cord blood transplants took place in New Zealand last year. One recipient was Ms Sharma.
Grateful for her good fortune, she is urging people to join the registry, as it may one day help someone else.
Becoming a donor
* To get on the bone marrow donor registry ring the Blood Service on 0800 GIVE BLOOD (0800 448 325).
* When you donate a unit of blood, tell the donor centre that you want to join the bone marrow donor registry, which is managed by the Leukaemia & Blood Foundation.
* All testing right up until the last minute is done with a sample of blood from your arm. Stemcells are never collected unless it is a full match, and a transplant is set to take place.