Information from loci can be used to determine how closely females are related to each other. The basic calculation of relatedness, developed by David Queller and Keith Goodnight (1989), has the following form:
The equation is summed over individuals, loci, and allelic position (2 positions for diploids, 1 for haploids). The variables are:
- P: population frequency of the allele present at the current locus & allelic position
- Px: frequency of the current allele in the current individual (i.e. 0.5 or 1 depending on whether the individual is a heterozygote or homozygote).
- Py: frequency of the current allele in the current individual's "partners."
Calculations can be carried out individually, or, for more extensive calculations, Relatedness , developed by Keith Goodnight, can be used. Relatedness is a Macintosh application for calculating relatedness statistics using the method of Queller & Goodnight (1989).
Relatedness calculates average genetic relatedness among sets of individuals defined by demographic variables, either on average or by pairs. It finds standard errors and confidence intervals for signifiance testing using a jackknife resampling method. It reads data sets in tab-formatted text files, which can be created using most spreadsheet or word processing programs. Data sets can include a variety of demographic variables identifying the individuals for which relatedness is to be calculated.
Relatedness is available for Macintosh only
Download "Relatedness"
For more information on the relatedness calculation, see
- Conducting the Relatedness Calculation
For more information on Relatedness 4.2, see
Though a complete manual for Relatedness 5.0 is included on the distribution disk, this document gives a brief overview of the program's basic features.