Axel E. Nielsen

Application of the iPLEXTM Gold SNP genotyping method for the analysis of Amerindian ancient DNA samples: Benefits for ancient population studies

Important developments in the matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOF MS) technique have generated new perspectives regarding SNP genotyping, which are particularly promising for ancient population‐based studies. The main aim of the present study was to investigate the application of a MALDI‐TOF MS‐based SNP genotyping technique, called iPLEX® Gold, to analyze Amerindian ancient DNA samples. The first objective was to test the sensitivity of the method, which is recommended for DNA quantities between 10 and 5 ng, for ancient biological samples containing DNA molecules that were degraded and present in minute quantities. The second objective was to detail the advantages of this technique for studies on ancient populations. Two multiplexes were designed, allowing the major Amerindian mitochondrial and Y haplogroups to be determined simultaneously. This analysis has never been described before. Results demonstrated the reliability and accuracy of the method; data were obtained for both mitochondrial and nuclear DNA using picogram (pg) quantities of nucleic acid. This technique has the advantages of both MS and minisequencing techniques; thus, it should be included in the protocols for future ancient DNA studies.

Poor Chiefs: Corporate Dimensions of Pre-Inca Society in the Southern Andes

During the first centuries of the second millennium AD, the people of the Southern Andes experienced dramatic organizational changes. The nature of this transformation, however, and of the social order that emerged from it, have been hard to define. I argue that these difficulties derive from the inability of Neo-evolutionary typologies to apprehend the structuring principles of pre-Hispanic society. The ethnohistorical sources suggest that, in the sixteenth century, Andean formations held a strong corporate orientation and followed segmentary, decentralized principles of integration, in which kin groups (ayllus) maintained certain control over strategic resources and local authorities, even when they were incorporated into larger polities or ethnic federations. Inequalities probably existed, but were based on the differential access to social and symbolic (political) capital, rather than on the control and accumulation of economic resources. Elements of this model are evaluated with archaeological data generated through the investigation of public spaces of the 13th and 14th centuries in Los Amarillos (NW Argentina) and Laqaya (SW Bolivia). The results indicate that some of these structuring principles may be traced back to pre-Inca times in the area, but they also suggest that there were significant differences between regions.