Oct. 18 (HealthDay News) -- The second phase of the HapMap Project -- created to identify and catalog genetic similarities and differences among populations around the world -- has been completed by scientists from six countries.

The first phase, completed in 2005, provided data that's led to the development of techniques used in the search for genes associated with common diseases. It's also helped in the identification of 50 such disease-associated genes.

"The original HapMap provided the backbone for genome-wide association studies that have uncovered previously unsuspected genetic components of many diseases, leading to new areas of research," Mark Daly, of the Massachusetts General Hospital (MGH) Center for Human Genetic Research, said in a prepared statement.

"The second phase has tripled the amount of genetic variation assessed and describes up to 95 percent of common single-letter variations in the human genetic code," said Daly, co-author of a report in the Oct. 18 issue of Nature.

Using data and methods based on the HapMap, MGH researchers in the past year have published studies outlining new genetic contributors to Crohn's disease, type 2 diabetes, prostate cancer, rheumatoid arthritis, multiple sclerosis and elevated blood cholesterol.

Information in the HapMap is accessible to scientists worldwide. Data from the project's second phase was added to the database as it became available and has already been used in numerous research studies.

SOURCE: Massachusetts General Hospital, news release, Oct. 16, 2007