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  • The Impact of Sample Size and Population History on Observed Mutational Spectra: A Case Study in Human and Chimpanzee Populations
Title: The Impact of Sample Size and Population History on Observed Mutational Spectra: A Case Study in Human and Chimpanzee Populations
Abstract Recent studies have highlighted variation in the mutational spectra among human populations as well as closely related hominoids—yet little remains known about the genetic and nongenetic factors driving these rate changes across the genome. Pinpointing the root causes of these differences is an important endeavor that requires careful comparative analyses of population-specific mutational landscapes at both broad and fine genomic scales. However, several factors can confound such analyses. Although previous studies have shown that technical artifacts, such as sequencing errors and batch effects, can contribute to observed mutational shifts, other potentially confounding parameters have received less attention thus far. Using population genetic simulations of human and chimpanzee populations as an illustrative example, we here show that the sample size required for robust inference of mutational spectra depends on the population-specific demographic history. As a consequence, the power to detect rate changes is high in certain hominoid populations while, for others, currently available sample sizes preclude analyses at fine genomic scales.  more » « less
Award ID(s):
2045343
PAR ID:
10487525
Author(s) / Creator(s):
; ; ; ;
Editor(s):
Baer, Charles
Publisher / Repository:
Oxford University Press on behalf of Society for Molecular Biology and Evolution
Date Published:
Journal Name:
Genome Biology and Evolution
Volume:
15
Issue:
3
ISSN:
1759-6653
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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