Ages of mutations on a coalescent tree.
Using the coalescent process, DNA sequences of a sample of individuals can be used to study the phylogenetic history of the individuals. Under the infinitely-many-sites mutation model, the DNA sequence data can be summarized by the number of segregating sites (which is numerically equivalent to the number of mutations on the tree). A number of methods exist, including a recursive method presented in this paper, that obtain an estimate of the age of the most recent common ancestor (MRCA), given the number of mutations. This paper introduces a method for finding the ages of mutations, given the total number of mutations on the tree. While the result is not useful in estimating the age of a specific segregating site, it is useful in examining the underlying assumption of a relatively constant population over time. This utilization of the result is illustrated using DNA sequence data obtained from a sample of Amerindians of the Nuu-Chah-Nulth tribe.
Thomson
R
R
Mathematics Department, Monash University, Clayton, Vic., Australia. rjt@mws4.biol.berkeley.edu
D001483:Base Sequence / Q000235:genetics*; D001955:British Columbia; D004272:DNA, Mitochondrial / Q000235:genetics; D005260:Female; D005828:Genetics, Population; D006801:Humans; D007198:Indians, North American / Q000235:genetics*; D008297:Male; D008390:Markov Chains; D008954:Models, Biological; D009154:Mutation / Q000235:genetics*; D009716:Numerical Analysis, Computer-Assisted; D010802:Phylogeny; D016012:Poisson Distribution; D011157:Population Dynamics; D014861:Washington
D004272:DNA, Mitochondrial