A connection to the past

Mar 25, 2008 18:06 GMT  ·  By

What does Latino mean? A new genetic analysis published in the online journal PLoS Genetics explains: 50% White from the father's side and 50% Amerindian or Black from the mother's side.

The research investigated the ancestry across Latin America and even if a significant differentiation between regions was found, the DNA shows a "genetic continuity" between pre- and post-Columbian populations. The study also explains the variation in the genome of the Latin American populations, caused by the colonization. This international research involved universities across Latin America, the US and Europe, and was coordinated by Dr. Andres Ruiz-Linares from University College London.

The European colonization of the Americas started in the late 15th century, and not only it changed the social and political models of the pre-Columbian America, but changed dramatically its composition, from an 100% Native American population to an over 50% mixed population.

The genetics of these violent changes now can be explained using new molecular tools. Genetic markers were studied in over 300 individuals from 13 mestizo populations in 7 Latin American countries, from Mexico to Chile. The genetic composition of ancestry widely varied amongst areas, connected to the time and intensity of European colonization.

Overall, it appeared that the first generation of the new colonies was mothered mainly by Native and African women, while being fathered by European men. This fits the historical argument that European colonizers killed off large numbers of native men and had sex with native women or with African slaves.

Even centuries later, the researchers could connect the Amerindian genetic inheritance of the Mestizos to local (in many cases now extinct) native populations that gave the local gene flow. Centuries of migrations and movements have not erased this.

The study "goes some way to rescuing the past of Latin America and the living presence of Native Americans throughout the region. Despite many past attempts to erase Native Americans from the history of the Latin America, the new research shows there is substantial genetic continuity between the pre- and post-Columbian populations," said Ruiz-Linares.

Besides providing a connection with the past, the research can signal the genetic patterns for diseases connected to Native Americans and Europeans. This research investigated populations from areas inhabited mostly by Native Americans and Europeans, but not those with significant Black immigration.