Genes of Large Effect and the Shape of the Distribution of a Quantitative Character

Abstract

The shape of the frequency distribution of a quantitative character will be non-normal if genes of large effect make an appreciable contribution to the variance of that character. The skewness coefficient will be dependent upon the relative frequencies of high and low alleles, while the kurtosis coefficient is negative for intermediate and positive for extreme frequencies of these genes. Two special models are considered in illustration.