Composite likelihood method for inferring local pedigrees.

Pedigrees contain information about the genealogical relationships among individuals and are of fundamental importance in many areas of genetic studies. However, pedigrees are often unknown and must be inferred from genetic data. Despite the importance of pedigree inference, existing methods are lim...

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Bibliographic Details
Published in:PLOS Genetics
Main Authors: Amy Ko, Rasmus Nielsen
Format: Article in Journal/Newspaper
Language:English
Published: Public Library of Science (PLoS) 2017
Subjects:
Online Access:https://doi.org/10.1371/journal.pgen.1006963
https://doaj.org/article/e8de59edc3754676b58b7c38d0b2a51a
Description
Summary:Pedigrees contain information about the genealogical relationships among individuals and are of fundamental importance in many areas of genetic studies. However, pedigrees are often unknown and must be inferred from genetic data. Despite the importance of pedigree inference, existing methods are limited to inferring only close relationships or analyzing a small number of individuals or loci. We present a simulated annealing method for estimating pedigrees in large samples of otherwise seemingly unrelated individuals using genome-wide SNP data. The method supports complex pedigree structures such as polygamous families, multi-generational families, and pedigrees in which many of the member individuals are missing. Computational speed is greatly enhanced by the use of a composite likelihood function which approximates the full likelihood. We validate our method on simulated data and show that it can infer distant relatives more accurately than existing methods. Furthermore, we illustrate the utility of the method on a sample of Greenlandic Inuit.