Indigenous Diversity in Mexico

One under appreciated fact about Mexico is the incredible indigenous diversity in the country.  When Kevin and I lived there, we loved having the opportunity to be able to visit pre-Columbian archeological sites from a range of different cultures.  What I didn’t realize was just how diverse the country really is.

For starters, Mexico has 65 different indigenous ethnic groups.  Scientists are starting to map the different genomes of 20 of these groups and have found remarkable differences across them, probably due to “centuries of living so far apart—and often in isolation because of mountain ranges, vast deserts, or other geographic barriers.”

Initial results, just published in Science, show that “the most divergent indigenous groups in Mexico are as different from each other as Europeans are from East Asians.”  And even though much of the population is now mestizo, “the mestizo genomes “track so well with the indigenous groups that we could use the genetic diversity in mestizos to make inferences about [their native] ancestors.”

Besides tracking what the historical movements of indigenous groups, the researchers hope to find clinical applications from their findings:

“Many of these variants are what he calls “globally rare but locally common.” That is, a genetic variant that’s widespread in one ethnic group, like the Maya, may hardly ever show up in people of different ancestry, like people of European descent. If you study the genomes of only the Europeans, you’d never catch the Maya variant. And that’s a big problem for people with Maya ancestry if that variant increases their risk of disease or changes the way they react to different kinds of medication.”