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Title: Oral metagenomes from Native American Ancestors reveal distinct microbial lineages in the pre‐contact era
Abstract Objectives

Limited studies have focused on how European contact and colonialism impacted Native American oral microbiomes, specifically, the diversity of commensal or opportunistically pathogenic oral microbes, which may be associated with oral diseases. Here, we studied the oral microbiomes of pre‐contact Wichita Ancestors, in partnership with the Descendant community, The Wichita and Affiliated Tribes, Oklahoma, USA.

Materials and Methods

Skeletal remains of 28 Wichita Ancestors from 20 archeological sites (dating approximately to 1250–1450 CE) were paleopathologically assessed for presence of dental calculus and oral disease. DNA was extracted from calculus, and partial uracil deglycosylase‐treated double‐stranded DNA libraries were shotgun‐sequenced using Illumina technology. DNA preservation was assessed, the microbial community was taxonomically profiled, and phylogenomic analyzes were conducted.

Results

Paleopathological analysis revealed signs of oral diseases such as caries and periodontitis. Calculus samples from 26 Ancestors yielded oral microbiomes with minimal extraneous contamination. Anaerolineaceae bacterium oral taxon 439 was found to be the most abundant bacterial species. Several Ancestors showed high abundance of bacteria typically associated with periodontitis such asTannerella forsythiaandTreponema denticola. Phylogenomic analyzes of Anaerolineaceae bacterium oral taxon 439 andT. forsythiarevealed biogeographic structuring; strains present in the Wichita Ancestors clustered with strains from other pre‐contact Native Americans and were distinct from European and/or post‐contact American strains.

Discussion

We present the largest oral metagenome dataset from a pre‐contact Native American population and demonstrate the presence of distinct lineages of oral microbes specific to the pre‐contact Americas.

 
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Award ID(s):
2045308
PAR ID:
10475999
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
American Journal of Biological Anthropology
Volume:
182
Issue:
4
ISSN:
2692-7691
Format(s):
Medium: X Size: p. 542-556
Size(s):
p. 542-556
Sponsoring Org:
National Science Foundation
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