Population genetics: Coalescence theory I
نویسنده
چکیده
To understand inferences based on sampling random relationships among a small sample of individuals of a contemporary population we need to know some basic models of population history. Several such models exist. Fisher (1929, and 1930) and Wright (1931) developed independently a simple population model. We call this model the Wright-Fisher population model. Alternatives are the Moran model, developed by Moran in 1958. A model that extends the Wright-Fisher model was found by Cannings in 1974. We will discuss the three models
منابع مشابه
Fumio Tajima and the Origin of Modern Population Genetics.
A fundamental concept in population genetics is the representation of the evolutionary history of a sample, of a single locus, as a tree. The theory describing such trees is called “coalescence theory,” and the primary mathematical model used is called “the coalescent,” or sometimes “Kingman’s coalescent,” as it was first discovered by the British mathematician Kingman (1982a,b). Coalescence th...
متن کاملA genealogical interpretation of linkage disequilibrium.
The degree of association between alleles at different loci, or linkage disequilibrium, is widely used to infer details of evolutionary processes. Here I explore how associations between alleles relate to properties of the underlying genealogy of sequences. Under the neutral, infinite-sites assumption I show that there is a direct correspondence between the covariance in coalescence times at di...
متن کاملCoalescence-Time Distributions in a Serial Founder Model of Human Evolutionary History
Simulation studies have demonstrated that a variety of patterns in worldwide genetic variation are compatible with the trends predicted by a serial founder model, in which populations expand outward from an initial source via a process in which new populations contain only subsets of the genetic diversity present in their parental populations. Here, we provide analytical results for key quantit...
متن کاملCoalface: a Graphical User Interface Program for the Simulation of Coalescence
In this manuscript I describe a computer program that simulates the coalescent process and provides visual outputs of coalescent genealogies to the screen. CoalFace is a user-friendly program for teaching the principles of coalescence to both undergraduate and postgraduates in population genetics. In addition, CoalFace can generate data for distributions of the time to the most recent common an...
متن کاملExpected coalescence times and segregating sites in a model of glacial cycles.
The climatic fluctuations of the Quaternary have influenced the distribution of numerous plant and animal species. Several species suffer population reduction and fragmentation, becoming restricted to refugia during glacial periods and expanding again during interglacials. The reduction in population size may reduce the effective population size, mean coalescence time and genetic variation, whe...
متن کامل