Behind the Science


The fossil record places human origins in Africa, but science continues to search for details about the incredible journey that took Homo sapiens to the far reaches of the Earth. How did each of us end up where we are? Why do we have such a wide variety of colors and features?

Picture of young girls in colorful African dress in ChadSuch questions are even more remarkable in light of genetic evidence that we are all descended from a common African ancestor who lived only 140,000 years ago.

Through the eons of time, the full story remains clearly written in our genes. When DNA is passed from one generation to the next, most of it is recombined by the processes that give each of us our individuality. But some parts of the DNA chain remain largely intact through the generations, altered only occasionally by random mutations, which become what are called genetic markers. The order in which these markers occur allows geneticists to trace our common evolutionary time line back many generations.

Different populations carry distinct genetic markers. Following the markers through the generations reveals a genetic tree on which today’s many diverse branches can be followed backward to their common African root.

The markers still present in our genes allow us to chart ancient human migrations from Africa across the continents. Through these markers, we can see living evidence of an ancient trek to populate the globe.

Next Generation GenoChip

The Genographic Project has just developed a cutting-edge new tool we called the Next Generation GenoChip, which has been designed for the study of genetic anthropology. Using scientific information gleaned from the first phases of the Genographic Project, it included a unique collection of more than 750,000 markers that we believe offer the richest ancestry-relevant information.

Picture of the GenoChip

This advanced technology enables us to determine new components of ancestry, with thousands of newly-identified markers on the Y chromosome, and provides extraordinary mitochondrial DNA resolution. It allows us to decipher the regional affiliations of mixed populations, enabling you to learn what percentage of your genome is affiliated with specific geographic regions around the world.

Learn more about the science behind the Genographic Project in the genetics overview on the following page.


Photographs by: David Evans (Chadian girls), Becky Hale (Geno Chip)