A new type of genomic map, known as the haplotype map, promises to speed the search for elusive genes involved in complex diseases. But some geneticists question whether it will work.

The so-called ‘HapMap’ is based on the assumption that common diseases are caused by common mutations of the human genome. New research shows that these mutations tend to be grouped together in so-called haplotype blocks which are remarkably consistent across different populations (see New research 'may speed up search for disease genes').

Proponents of the map say it’s the best hope for tracking down the genes involved in common diseases. “This is the single most important genomic resource for understanding human disease after the [human genome] sequence,” says Francis Collins, director of the US National Human Genome Research Institute.

But many researchers say it’s an untested concept that is not worth the estimated US$110 the project is likely to need.

Reference: Science 296, 1391 (2002)