Bioanthropological analysis of human remains from the archaic and classic period discovered in Puyil cave, Mexico.

OBJECTIVES: Determine the geographic place of origin and maternal lineage of prehistoric human skeletal remains discovered in Puyil Cave, Tabasco State, Mexico, located in a region currently populated by Olmec, Zoque and Maya populations. MATERIALS AND METHODS: All specimens were radiocarbon (14C) dated (beta analytic), had dental modifications classified, and had an analysis of 13 homologous reference points conducted to evaluate artificial cranial deformation (ACD). Following DNA purification, hypervariable region I (HVR-1) of the mitogenome was amplified and Sanger sequenced. Finally, Next Generation Sequencing (NGS) was performed for total DNA. Mitochondrial DNA (mtDNA) variants and haplogroups were determined using BioEdit 7.2 and IGV software and confirmed with MITOMASTER and WebHome softwares. RESULTS: Radiocarbon dating (14C) demonstrated that the inhabitants of Puyil Cave lived during the Archaic and Classic Periods and displayed tabular oblique and tabular mimetic ACD. These pre-Hispanic remains exhibited five mtDNA lineages: A, A2, C1, C1c and D4. Network analysis revealed a close genetic affinity between pre-Hispanic Puyil Cave inhabitants and contemporary Maya subpopulations from Mexico and Guatemala, as well as individuals from Bolivia, Brazil, the Dominican Republic, and China. CONCLUSIONS: Our results elucidate the dispersal of pre-Hispanic Olmec and Maya ancestors and suggest that ACD practices are closely related to Olmec and Maya practices. Additionally, we conclude that ACD has likely been practiced in the region since the Middle-Archaic Period.

A novel method of male sex identification of human ancient skeletal remains.

Sex identification of ancient individuals is important to understand aspects of the culture, demographic structure, religious practices, disease association, and the history of the ancient civilizations. Sex identification is performed using anthropometric measurements and molecular genetics techniques, including quantification of the X and Y chromosomes. These approaches are not always reliable in subadult, or fragmented, incomplete skeletons or when the DNA is highly degraded. Most of the methods include the identification of the male and female sexes, but the absence of a specific marker for the males does not mean that the sample obtained was from a female. This study aims (1) to identify new male-specific regions that allow male identification; (2) to contrast the effectiveness of these markers against AMELX/AMELY and anthropometric measurement procedures; and (3) to test the efficacy of these markers in archaeological samples. For the first two aims, we used known sex samples, and for the third aim, we used samples from different archaeological sites. A novel molecular technique to identify male-specific regions by amplification of TTTY7, TSPY3, TTTY2, and TTTY22 genes of the human Y chromosome was developed. The results showed amplification of the specific DNA regions of Y chromosome in male individuals, with no amplification being observed in any of the female samples, confirming their specificity for male individuals. This approach complements the current procedures, such as the AMELX/AMELY test and anthropometric principle.