To the editor:

The Gambian National DNA Bank, the first National Bio-Bank developed in Africa, was funded in November 2000 by the Medical Research Council (MRC) as one of 14 DNA collection sites established to study the genetics of complex diseases. One of these sites is housed at the MRC Laboratories in The Gambia and has a special, though not exclusive, focus on malaria, HIV and tuberculosis. Additional projects include analyses of genome diversity in West African populations and a collection of twin-sister pairs to study the genetic basis of dizygotic twins (∼ 2% of live births in the country). So far, more than 30,000 DNA samples have been collected, with many ongoing studies and more planned.

For the first time in a sub-Saharan country, a centralized structure and database for archiving DNA samples has been created, in collaboration with the Jean Dausset Foundation-CEPH. The bank is regulated by guidelines (Supplementary Note online) for sample collection, archiving, data storage and privacy protection, which were developed and approved by the MRC, the MRC Laboratories Scientific Coordinating Committee and by the Gambia Government/MRC Joint Ethics Committee. The Guidelines, which are enforced by these Committees, stemmed from the need to adapt to the local reality the many existing recommendations on bio-banking, privacy protection, genetics research and, generally, on medical research in developing countries (http://www3.who.int/whosis/genomics/pdf/genomics08.pdf, http://www.mrc.ac.uk/pdf-devsoc.pdf, http://www.mrc.ac.uk/pdf-tissue_guide_fin.pdf, http://www.nuffieldbioethics.org/publications/pp_0000000013.asp).

The Gambian DNA Bank promotes sharing of information and resources with centers around the world, and one of its ultimate goals is health improvement. In the short term, benefits should accrue to the participants in the studies. A recent example is a large project on genetic and environmental factors for susceptibility to tuberculosis, designed as a household association and family-based study and carried out in The Gambia, Guinea-Bissau and Guinea-Conakry1. The project focused on the systematic detection of tuberculosis cases in the families of individuals with tuberculosis and controls. Clinical services were considerably augmented within the framework of the genetic study, to the benefit of the populations involved.

During research projects at the MRC Unit in The Gambia, biological samples (mostly blood, buffy coats and peripheral blood mononuclear cells) were taken and stored at a time when molecular genetics was still in its infancy. The process of obtaining consent has evolved enormously over time, and in the past, samples may have been taken from subjects who were not made specifically aware that the samples were going to be used for genetic studies. The Guidelines now regulate the use of these archived DNA specimens: in almost all circumstances they can be used only after anonymization and unlinking (Supplementary Note online), and all use requires approval by the Ethics Committee.

Regrettably, most African countries do not have the infrastructure necessary to carry out genomic studies, and so most scientific exchange has taken place with developed countries. The Ethics Committee has a key role in sanctioning shipment of any samples to external collaborators. The Committee evaluates the specificity of the project and re-evaluates projects in case their focus changes over time. All transfer of DNA samples to collaborators is accompanied by signed agreements and detailed documentation describing the projects involved. The review of sample transfer to third parties is compulsory and is not permitted from one collaborator to another without consent of the Ethics Committee.

In the long term, understanding genetic determinants of infection can lead to prevention and improved treatment, but this does not mean that genetic research will cure infectious diseases. Even more complicated is the situation of population-genetics studies promoted by interest in the greater genomic diversity found in Africans compared with Europeans and Asians, and consistent with the hypothesis of an African origin of modern humans. Where sampling is not part of research aimed directly at disease, the connection to health interventions seems weak. But this does not imply that studies on genome diversity should not be done, for the contribution of both inter- and intraethnic genetic variability comparisons is crucial in our understanding of immunity to infections. For example, the findings that West African Fulani have fewer malaria attacks and lower parasitemia by Plasmodium falciparum than two sympatric ethnic groups2, and that they have intragroup variation in immune responses to malaria3, open the possibility of identifying genetic factors determining malarial immunity. Immunogenetic associations with infectious disease, such as the association between HLA-B53 and resistance to severe malaria found in Gambian children4, can affect vaccine development.

The ethics guidelines adopted for the Gambian National DNA Bank do not presume to be the last word on the matter. Rather, we hope their publication will stimulate discussion of the appropriate way to regulate genomic research in developing countries. We hope that our initiative will be seen as an important experience in a complex and fast-evolving venture from which Africa should not be excluded, and as a possible template to be adapted by similar initiatives in other parts of the world.

Note: Supplementary information is available on the Nature Genetics website.