ALRATIO - R script for the analysis of relation between the effective and the detected number of alleles
It is widely accepted that understanding the heterogeneity of a population is important in assessment of the vulnerability of a conservation unit (Frankham et al., 2002). Standard measures such as estimation of heterozygosity, deviations from Hardy–Weinberg equilibrium, effective population size, inbreeding coefficients are widely used. Minor, but very important elements of these measures are allelic diversity, effective number of alleles and allelic richness which characterize the extent of genetic diversity. Allelic diversity (An) represents an average number of alleles per locus determined by direct count. When more than one locus is considered, it is calculated as a number of alleles averaged over loci expressed as k/l where k is the total number of alleles determined at all the observed loci and l is the number of loci (Frankham et al., 2002). The effective number of alleles (Ae) is a measure that shows the number of alleles required to ensure the same level of heterozygosity under the assumption of balanced allele frequency and low influence of rare alleles. It is expressed as 1/Σpi 2