Gene 'Map' of Mexicans Reveals Great Diversity

There is vast genetic diversity among Mexicans, and some groups of people in the country are as different from one another as Europeans are from East Asians, a new study shows.

The findings call into question the current practice of grouping all Mexicans or Hispanics together as a single group for genetic, clinical or population studies, the team of international investigators said.

"Mexico harbors one of the largest amounts of pre-Columbian genetic diversity in the Americas," study co-author Dr. Andres Moreno-Estrada, a life sciences research associate at Stanford University, said in a university news release. "For the first time, we've mapped this diversity to a very fine geographic scale."

The researchers conducted genetic analyses of 511 people representing 20 indigenous populations from across Mexico, 500 people of mixed Mexican, European and African heritage from 10 Mexican states, a region of Guadalajara and Los Angeles, as well as people from 16 European populations and the Yoruba people of West Africa.

"We're moving beyond blanket definitions like Mexican or Latino," Moreno-Estrada said. "Now we're putting finer details on that map. Those broad terms imply common ground among populations, but we're finding that it's much more like a mosaic."

The results could help influence health care and public health policies, the team added.

"Understanding the genetic structure of a population is important for understanding its population history, as well as designing studies of complex biomedical traits, including disease susceptibility," explained study co-senior author Carlos Bustamante, a professor of genetics at Stanford.

"As we deploy genomics technology in previously understudied populations like those of Latin America, we discover remarkable richness in the genetic diversity of these important groups and why it matters for health and disease," he added.

One particularly notable finding of the study is that genetic variations in Native American ancestry among Mexicans and Mexican Americans have a major effect on biomedical traits, such as lung function.

The study appears in the June 13 issue of the journal Science.

More information

The U.S. National Library of Medicine has more about genetics.