The Approximate Variance of Correlation Measures of Linkage Disequilibrium

Abstract

A delta method approximation is utilized to produce the variance formula of the correlation measure of Linkage Disequilibrium for four types of genetic data. These data types include gametic and genotypic counts, with different assumptions used to simplify the analysis of the genotypic counts. In each case the variance formula is derived and plotted for several choices of the allele frequencies and for all feasible values of ρ. Simulations are carried out to compare the variance of simulated Linkage Disequilibrium correlation values to the theoretical variance formula. Results indicate that the variance formulae are good approximations for each type of genetic data. Fisher’s transformation improved the approximation in some cases.