ONCOLOGY RESEARCH

Bone marrow registry - need of the hour, say experts

Shardul Nautiyal - Mumbai

India urgently needs more bone marrow(BM) registries to ensure immediate access to matching bone marrow, for patients suffering from gentic blood disorders, suggest experts. They emphasise that public should be educated about the existence and methodology of such a set up, which would enable voluntary BM donation in the country for the expansion of current BM donor database in the world. The current BM database of 89 lakh BM donors existing in the registries across the world have a very poor representation of the Indian BM donors.
As of now, countries like Australia, Japan, France, Germany, Scandinavia, Italy, Holland, US (National Marrow Donor Program) and UK (Anthony Nolan Donor Marrow Registry) maintain big registries. The 89 lakh bone marrow database of the world is existing in the form of these registries.
A bone marrow (BM) registry is a collection of ‘voluntary healthy donors’ willing to donate their bone marrow (or stem cells) to the patient if their HLA phenotypes (or HLA profile) match cent per cent. As of now, only two bone marrow registries exist. One is at Tata Memorial Hospital, Mumbai and the other at All India Institute of Medical Sciences (AIIMS), New Delhi.
The need for the registry stems from the fact that many patients do not find a match within the family and the community. Therefore, they are left with no option but to seek BM transplant from outside. Says Dr S B Rajadhyaksha, head, department of transfusion medicine, Tata Memorial Hospital, “BM transplantation is hampered as probability of finding a donor match within a family is only 25 per cent. Many patients would have to undergo other modes of therapy or find an unrelated matched donor. Besides this government may not find the urgency for a BM registry as it has other priorities.”
According to Dr N K Mehra, head, department of transplant immunology and immunogenetics, AIIMS, a bone marrow registry is required because of the ethnic diversity of the Indian population. “We need a marrow registry in India because of the unique genetic make up of the population of India, particularly as far as the HLA diversity is concerned,” says he.
The chances of any two unrelated individuals matching are between 1 in 100 to 1 in a million depending on how frequently the individual’s antigens are found in the population. Extensive genomic studies conducted at AIIMS has revealed several “novel HLA genes” and “unique HLA haplotypes” in Indian population making a person of Indian origin at a lesser chance of finding a HLA ’full house’ matched donor and 20 per cent less chance than their Caucasian counterpart from the available pool of 8.9 million donors around the world.
Marrow transplantation is the only cure for many diseases such as leukaemia, aplastic anaemia, thalassaemia and other haematological malignancies, say experts. More than 60 potentially fatal diseases including several types of leukaemia are treated with unrelated marrow transplants. Overall survival rates for diseases that would inevitably be fatal without transplantation is 40 to 50 per cent. Marrow transplants are used to treat patients whose marrow stops producing the correct amounts of various blood cells.
To set up a bone marrow registry, one requires to have HLA testing facilities including DNA-based technologies, donor recruitment drives, a computer set up with a systems analyst, scientists, technicians and an advisory board. The cost of setting up such a registry is Rs 20-30 lakh. “It should be established in an academic institution without any commercial interests. Ministry of Health through the Indian Council of Medical Research (ICMR) should take an initiative in setting up such a registry,” says Dr Mehra.
Tata Memorial hospital is equipped with facilities which are basic to a bone marrow Registry. At AIIMS, the Asian Indian Donor Marrow Registry (AIDMR) is existing since 1994, with a current bone marrow database of 3,000 donors. This registry, which was founded by Dr Mehra as the chairman, has functional links with all other registries around the world. “As the registries across the world are networked, we want that the public in India should be educated about the need for a BM registry. Social organisations, planners, economists and medical fraternity should come forward in helping expand the registry by funding and making public aware” Dr Mehra added. Box
HLA typing is based on the concept that the genetic trait used for matching is HLA. HLA is a protein found on the surface of White Blood Cells(WBC) and other tissues. The patient’s and the donor’s HLA is matched in the process. There are HLA-A, B, C and DR antigens. Each individual has two sets of these antigens, one set inherited from each parent. For this reason, it is much more likely for a brother or sister to match the patient. It is most likely to find a matched donor within the same racial or ethnic group as well. The cost of a HLA typing ranges from Rs 3,000 to 10,000.

shardulnautiyal@rediffmail.com