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What is the International HapMap Project?

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The International HapMap Project was launched in October 2002 as a scientific effort to identify common genetic variations among people. This project was a collaboration of scientists from public and private organizations in six countries. The HapMap Project released its third and final dataset in 2009. While this project is no longer active, data that was collected from the project is still freely available to researchers worldwide. Researchers can use the data to learn more about the relationship between genetic differences and human disease.

The project created a HapMap (short for “haplotype map”), which is a catalog of common genetic variants called single nucleotide polymorphisms or SNPs (pronounced “snips”).  Each SNP represents a difference in a single DNA building block, called a nucleotide. These variations occur normally throughout a person’s DNA. When several SNPs cluster together on a chromosome, they are inherited as a block known as a haplotype. The HapMap describes haplotypes, including their locations in the genome and their frequency in different populations throughout the world.    

The human genome contains roughly 4 to 5 million SNPs. It would be difficult, time-consuming, and expensive to look at each of these changes and determine whether it plays a role in human disease. Using haplotypes, researchers can sample a selection of these variants instead of studying each one. The HapMap helped to make carrying out large-scale studies of SNPs and human disease (called genome-wide association studies) cheaper, faster, and less complicated. 

The main goal of the International HapMap Project was to describe common patterns of human genetic variation that are involved in human health and disease. Additionally, data from the project can be used to find genetic differences that can help predict an individual’s response to particular medicines or environmental factors (such as toxins.)


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