AncestryDNA uses two different processes to determine the regions provided in your DNA Story: a reference panel and Genetic Communities.
Building reference panel
One way we create estimates of your genetic ethnicity is by comparing your DNA to the DNA of other people who are native to a region. The AncestryDNA reference panel contains 3,000 DNA samples from people from around the world.
We build the reference panel from a larger reference collection of 4,245 DNA samples collected from people whose genealogy suggests they are native to one region. Many of these samples were originally collected by the Sorenson Molecular Genealogy Foundation (read more). The images below show the process of gathering local samples from various parts of the world.
Each panel member's genealogy is documented so we can be confident that their family is representative of people with a long history (hundreds of years) in that region.
Each volunteer's DNA sample from a given region is then tested and compared to all the others to construct the AncestryDNA reference panel. In the end, 3,000 of 4,245 individuals were chosen for the AncestryDNA reference panel.
We compare your DNA to the reference panel
We then compare your DNA to the DNA in the reference panel to see which regions your DNA is most like. The ethnicity estimate you see on the web site is the result of this comparison. (Learn more about how we create the ranges for your estimates)
Still curious to understand more? Cool--we're glad you're as interested in genetics as we are. Check out our white paper on ethnicity prediction.