

This is a comprehensive bibliography (under construction) of primary and secondary sources on the neutral theory of molecular evolution. It currently covers the period 19732001. 
Author :

Colgan, D. J.

Year :

1997

Title :

Estimating selective coefficients of allelic substitutions from patterns of interspecific allozymic mobility difference

Journal :

Heredity

Volume :

78

Pages :

655664

Date :

Jun

Short Title :

Estimating selective coefficients of allelic substitutions from patterns of interspecific allozymic

Alternate Journal :

Heredity

Custom 2 :

ISI:A1997XE87300011

Abstract :

The neutral hypothesis of molecular evolution predicts that there should be a 1:1 ratio between allozymes in a species which are faster or slower than allozymes at the corresponding loci in a second species. Methods are presented in this paper for estimating selective differentials from observed values of r, the deviation from a fraction of 1/2 in the proportion of substitutions conferring a mobility change in a specified direction. Although the methods were developed for allozymes, they are readily applied to cases where two taxa may differ in other properties, such as DNA sequence. r is related to the selection coefficient s under a 'genic selection' model. If a change in one direction is favoured in one species and a change in the other direction is equally favoured in the second species, both s and N are assumed constant and only one substitution has occurred at each locus, then the estimate of s is approximately (ln(1/2+r)ln(1/2r))/4N. If selective coefficients follow an unspecified distribution f(s) and N is assumed constant, then the average value of s lies between r/2N(1/2 + r) and r/2N(1/2  r). Specifying the distribution of s to enable point estimation of E(s) is mathematically difficult for the usual probability density functions. A new family of distributions is suggested to overcome these difficulties. The analysis is extended to cover estimation of r where more than one substitution has occurred. The range of the various estimates of s provided by these methods from electrophoretic data is usually below 1/N and mostly substantially so.

Notes :

Times Cited: 0
6
XE873
HEREDITY

  contributed by John Beatty, March 29, 2002 







