Comparison between morphological and genetic data to estimate biological relationship: The case of the Egyin Gol necropolis (Mongolia)

Abstract

Osseous and dental nonmetric (discrete) traits have long been used to assess population variability and affinity in anthropological and archaeological contexts. However, the full extent to which nonmetric traits can reliably be used as a proxy for genetic data when assessing close or familial relationships is currently poorly understood. This study represents the unique opportunity to directly compare genetic and nonmetric data for the same individuals excavated from the Egyin Gol necropolis, Mongolia. These data were analyzed to consider the general efficacy of nonmetric traits for detecting familial groupings in the absence of available genetic data. The results showed that the Egyin Gol population is quite homogenous both metrically and genetically confirming a previous suggestion that the same people occupied the necropolis throughout the five centuries of its existence. Kinship analysis detected the presence of potential family burials in the necropolis. Moreover, individuals buried in one sector of the necropolis were differentiated from other sectors on the basis of nonmetric data. This separation is likely due to an outside Turkish influence in the paternal line, as indicated by the results of Y-chromosome analysis. Affinity matrices based on nonmetric and genetic data were correlated demonstrating the potential of nonmetric traits for detecting relationships in the absence of genetic data. However, the strengths of the correlations were relatively low, cautioning against the use of nonmetric traits when the resolution of the familial relationships is low.

An evaluation of non-metric cranial traits used to estimate ancestry in a South African sample

“…Unlike osteometric stature or sexual dimorphism, they were not population specific. Similarly in a study on discrete traits and familial (genetic) relationships, Ricaut et al [18] found positivealbeit low -correlations between the two variables. In line with other researchers, they cautioned the use of discrete traits as a means to explain assumed genetic differences between groups.…”

“…Yet, many researchers are unsure about these traits being valid measures in discerning population differences, particularly among admixed groups such as ''Coloured'' South Africans [15][16][17][18].…”

Do nuclear DNA and dental nonmetric data produce similar reconstructions of regional population history? An example from modern coastal Kenya

“…Both acknowledge the value of skeletal variants in bioarchaeological studies at these geographic scales. Ricaut et al (2010) found that combined morphological data provided good resolution in identifying pairs of kin within a Mongolian necropolis, although genetic findings detected double the number. In the second study, Herrera et al (2014) compared Y-chromosome, mtDNA, cranial metric, and cranial morphology data in samples from the Bering Strait region; they found that craniometric distances were correlated with mtDNA, while distances based on cranial morphology were correlated with those from Ychromosome variants.…”

“…In the second study, Herrera et al (2014) compared Y-chromosome, mtDNA, cranial metric, and cranial morphology data in samples from the Bering Strait region; they found that craniometric distances were correlated with mtDNA, while distances based on cranial morphology were correlated with those from Ychromosome variants. Viewed as a whole, two lessons can be learned from the present and previous studies: 1) additional work needs to be undertaken to determine which skeletal and genetic data are best suited to answer particular research questions (Herrera et al, 2014;present study); and 2) care should be taken when formulating very fine scale interpretations of population history from skeletal data (Ricaut et al, 2010;present study;also Scott and Turner, 1997).…”

“…Two recent publications also examine the agreement between paired genetic and morphological data using archaeological samples. First, Ricaut et al (2010) examined mixed cranial and dental morphology samples to estimate kinship within a single site, while Herrera et al (2014) examined cranial metric and morphological variation to understand population history at a regional level. Both acknowledge the value of skeletal variants in bioarchaeological studies at these geographic scales.…”