Scientists create world's largest catalog.

• Position: 1000 Genomes Project

An international team of scientists from the 1000 Genomes Project Consortium has created the world's largest catalog of genomic differences among humans, providing researchers with powerful clues to help them establish why some people are susceptible to various diseases.

While most differences in peoples' genomes--called variants--are harmless, some are beneficial, while others contribute to diseases and conditions ranging from cognitive disabilities to susceptibilities to cancer, obesity, diabetes, heart disease, and other disorders. Understanding how genomic variants contribute to disease may help clinicians develop improved diagnostics and treatments, in addition to new methods of prevention.

Investigators examined the genomes from 26 populations across Africa, East and South Asia, Europe, and the Americas, identifying about 88,000,000 sites in the human genome that vary among people, establishing a database available to researchers as a standard reference for how the genomic makeup of people varies in populations and around the world. The catalog more than doubles the number of known variant sites in the human genome, and now can be used in a wide range of studies of human biology and medicine, providing the basis for a new understanding of how inherited differences in DNA can contribute to disease risk and drug response.

Of the variable sites identified, about 12,000,000 had common variants that were likely shared by many of the populations. The study showed that the greatest genomic diversity is in African populations, consistent with evidence that humans originated in Africa and that migrations from Africa established other populations around the world.

The 26 populations studied included groups such as the Esan in Nigeria; Colombians in Medellin, Colombia; Iberian populations in Spain...