[Mitochondrial DNA analysis on pre-Columbian bone remains of the Herrera period]

Ancient bone remains constitute an important source of biological information, and their genetic characterization allows the confirmation or rebuttal of human affiliations proposed on the basis of non-molecular approaches. Pre-Columbian history of the Eastern Andes in Colombia has been divided into three main periods: (i) an early colonization by groups of hunter-gatherers, (ii) an intermediate period "Herrera" characterized by primitive agriculture and (iii) a late stage of Chibcha-speaking groups, with agriculture and ceramics ("agroalfarero").

The mitochondrial DNA on ancient bone remains of the Herrera period were analyzed for comparison with modern and other ancient DNAs.

Mitochondrial DNA was extracted from 11 Herrera individuals [approximately 2,000 years before present (YBP)] found in the Madrid 2-41 archaeological site near Bogotá, Colombia. A 192 bp segment of the hypervariable segment I was amplified and sequenced, following stringent archaic DNA authenticity criteria. The sequences were compared with those in American and European databases using bioinformatics tools.

All individuals had identical sequences and were classified as haplogroup B. This identity may be related to the type of ritual burial performed in the site, probably exclusively for members of a hierarchically important family of the ancient Herrera society. The search for homologous sequences in the American and European mtDNA data bases produced no identical coincidences, although a Brazilian Amazonic individual (approximately 4,000 YBP) was recorded with a matching sequence.

Individuals buried in the Madrid 2-41 site were maternally closely related and showed a mtDNA sequence that is apparently absent in contemporary populations.