The haplotype map will be based on DNA samples obtained from hundreds of people in geographically distinct populations: Nigerian Yorubas, Han Chinese, Japanese, and US residents of European origin. These populations have been selected for their diverse population histories, which may result in differences in haplotype structure and frequencies, and are not meant to be representative of different ethnic or racial groups.

As with any genetic resource there are two primary concerns:

• consent and privacy
• misuse of the haplotype map, or results obtained from it.

The first issue is being addressed through a sampling strategy that places considerable importance on initial community engagement and information transfer. Potential donors will made aware of how samples will be collected and used, and advisory groups will remain in the communities after the samples have been obtained to provide continuous liaison.

Although each sample will be marked with the population of origin, there will be no information that can be used to identify individual donors. More samples will be collected than are required so that no-one will know whose DNA was actually used to develop the map.

The second issue is important because the HapMap Project will help to identify genetic variants associated with disease and drug responses. One danger is that variants more common in certain populations will be mistakenly used to characterise entire populations.

At an individual level, individuals may find themselves 'labelled' according to their haplotype characteristics with the possibility that too much emphasis will be placed on the presence of a particular haplotype (in most cases, the effects of particular SNP alleles are likely to be small, and their detrimental effects will be neither inevitable nor insuperable).

These problems, common to any human genetic study, call for clarity in the way the project and its results are communicated, and the HapMap Project includes resources specifically set aside for educational purposes. Specifically, a website is being set up to communicate the goals, rationale, and implications of the project, which will be updated regularly.

Links

The International HapMap Project