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Title: Do dental nonmetric traits actually work as proxies for neutral genomic data? Some answers from continental‐ and global‐level analyses
Abstract Objectives

Crown and root traits, like those in the Arizona State University Dental Anthropology System (ASUDAS), are seemingly useful as genetic proxies. However, recent studies report mixed results concerning their heritability, and ability to assess variation to the level of genomic data. The aim is to test further if such traits can approximate genetic relatedness, among continental and global samples.

Materials and Methods

First, for 12 African populations, Mantel correlations were calculated between mean measure of divergence (MMD) distances from up to 36 ASUDAS traits, andFSTdistances from >350,000 single nucleotide polymorphisms (SNPs) among matched dental and genetic samples. Second, among 32 global samples, MMD andFSTdistances were again compared. Correlations were also calculated between them and inter‐sample geographic distances to further evaluate correspondence.

Results

A close ASUDAS/SNP association, based on MMD andFSTcorrelations, is evident, withrmvalues between .72 globally and .84 in Africa. The same is true concerning their association with geographic distances, from .68 for a 36‐trait African MMD to .77 forFSTglobally; one exception isFSTand African geographic distances,rm= 0.49. Partial MMD/FSTcorrelations controlling for geographic distances are strong for Africa (.78) and moderate globally (.4).

Discussion

Relative to prior studies, MMD/FSTcorrelations imply greater dental and genetic correspondence; for studies allowing direct comparison, the present correlations are markedly stronger. The implication is that ASUDAS traits are reliable proxies for genetic data—a positive conclusion, meaning they can be used with or instead of genomic markers when the latter are unavailable.

 
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PAR ID:
10457592
Author(s) / Creator(s):
 ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
American Journal of Physical Anthropology
Volume:
172
Issue:
3
ISSN:
0002-9483
Page Range / eLocation ID:
p. 347-375
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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