Cris E. Hughes, Bridget F. B. Algee‐Hewitt, L. Konigsberg
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引用次数: 0
Abstract
The Combined DNA Index System (CODIS) loci comprise a standard microsatellite marker set widely used for distinguishing among individuals in forensic DNA identity testing for medicolegal casework in the United States and in other countries. In anthropological genetic research, CODIS markers have become an important tool for uses extending beyond case investigations to quantify ancestry proportions, reveals patterns of admixture, and trace population histories. These investigations are especially prevalent in studies of Latin American population structure. Nevertheless, the accuracy of the ancestry estimates computed from the CODIS loci for highly admixed Latino populations has not been formally tested. Longstanding arguments have been made that small ancestry panels, including the CODIS loci specifically, are not suitable for ancestry inference in admixed populations, due to high heterozygosity and limited number of loci used. Recent studies on ancestry inference using the CODIS loci suggest that these do confer more information of population-level identifiability than recognized in forensic genetic scholarship and by the medicolegal community. Here, we formally test the ability of CODIS and CODIS-proxy (e.g., high-heterozygosity and individual-identifiability loci) marker panels to accurately estimate admixture proportions of individuals, including a sample of Latinos with a wide range of ancestry proportions. Using the same individuals to make direct comparisons of the outcomes, the authors produced ancestry estimates from (a) a small CODIS/CODIS-proxy locus panel and (b) a robust and validated microsatellite ancestry-informative panel. They found evidence (e.g., ρ = 0.80–0.88) that supports the use of CODIS/ CODIS-proxy loci to capture the general ancestry estimation trends of a sample. This finding is in line with results of studies using CODIS on Latin American populations: the ancestry estimations generated by CODIS present trends supported by documented population histories (e.g., colonialism and population movements) and microevolutionary events (e.g., gene flow) in Latin America. However, this study also highlights the limitations of CODIS for making individual-level inferences of ancestry: the associated estimates for an acceptable level of statistical confidence (95%) are too broad to make any nuanced inferences regarding an individual’s actual ancestry composition.
期刊介绍:
Human Biology publishes original scientific articles, brief communications, letters to the editor, and review articles on the general topic of biological anthropology. Our main focus is understanding human biological variation and human evolution through a broad range of approaches.
We encourage investigators to submit any study on human biological diversity presented from an evolutionary or adaptive perspective. Priority will be given to interdisciplinary studies that seek to better explain the interaction between cultural processes and biological processes in our evolution. Methodological papers are also encouraged. Any computational approach intended to summarize cultural variation is encouraged. Studies that are essentially descriptive or concern only a limited geographic area are acceptable only when they have a wider relevance to understanding human biological variation.
Manuscripts may cover any of the following disciplines, once the anthropological focus is apparent: human population genetics, evolutionary and genetic demography, quantitative genetics, evolutionary biology, ancient DNA studies, biological diversity interpreted in terms of adaptation (biometry, physical anthropology), and interdisciplinary research linking biological and cultural diversity (inferred from linguistic variability, ethnological diversity, archaeological evidence, etc.).