Quantitative genetics

Quantitative genetics is the study of continuous traits (such as height or weight) and its underlying mechanisms. It is effectively an extension of simple Mendelian inheritance in that the combined effect of the many underlying genes results in a continuous distribution of phenotypic values.
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The statistical study of the genetics of quantitative characters (biometrical genetics) as opposed to Mendelian (discrete) characters. Quantitative genetic characters are those that do not assort in a simple way in crosses. Examples are physiological activity, reproductive rate, behavior, size, and height. A major task of quantitative genetics is to determine the ways in which genes interact with the environment to contribute to the formation of a given quantitative trait distribution (and the estimation of genetic and environmental variance). Link to a lecture on quantative genetics.