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The fourgamete test is based on the infinitesites model which assumes that the probability of the same mutation occurring twice (recurrent or parallel mutations) and the probability of a mutation back to the original state (reverse mutations) are close to zero. Without these types of mutations, the only explanation for observing the four dilocus genotypes (example below) is recombination (Hudson and Kaplan 1985, Genetics 111:147164). Thus, the presence of all four gametes is also called phylogenetic incompatibility.
Package details 


Author  Milton T Drott 
Maintainer  Milton T Drott <mtd66@cornell.edu> 
License  GPL2 
Version  0.1.0 
Package repository  View on CRAN 
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