Scientists are reporting a breakthrough in genetic research that may help speed up efforts to track common illnesses like heart disease and diabetes.

A report in the journal Nature details how researchers have been able to map patterns of tiny D-N-A differences in people.

Scientists hope to use genetic clues to find disease-related genes as a way to diagnose, predict and develop treatments. The genetic data gathering has already been used to track down a gene linked to the eye disorder macular degeneration.

Lead researcher Doctor David Altshuler of the Broad Institute in Boston says the so-called "Hap-Map" represents a "real sea change" in studying the genetics of disease.