Falconer formula

The Falconer formula is an estimation formula for determining the genetic heritability of personality traits, especially in twin studies .

It was developed in 1960 by the British geneticist Douglas Scott Falconer (1913-2004) and reads:

${\displaystyle h^{2}=2\cdot (r_{EZ}-r_{ZZ})}$

Herein stands for heredity in the broader sense; stands for the correlation of identical twins and the correlation of dizygotic twins (in English: MZ for monozygous and DZ for dizygous ). ${\displaystyle h^{2}}$ ${\displaystyle r_{EZ}}$ ${\displaystyle r_{ZZ}}$

The formula provides reasonable estimates if there is neither gene dominance , epistasis, or assortative mating and the environment contributes equally to the similarity of the identical and dizygotic twins.

example

With regard to one characteristic, the correlation for EZ is that for ZZ . How high can the heritability of the trait be estimated? ${\displaystyle r_{EZ}=0{,}50}$ ${\displaystyle r_{ZZ}=0{,}30}$

${\displaystyle h^{2}=2\cdot (0{,}50-0{,}30)=0{,}40}$

There are similar estimation formulas for heredity in the narrower sense as well as for shared and individual environments. Another variant for estimating heritability suggested by Holzinger .

literature

• Douglas Scott Falconer: Introduction to Quantitative Genetics . Addison-Wesley Pub Co Inc; Edition: 0004 (December 5, 1995). ISBN 0582243025