Power and sample size calculations for genetic association studies allowing
for misspecification of the model of genetic susceptibility.
Power and/or sample size can be calculated for logistic (case/control study design)
and linear (continuous phenotype) regression models, using additive, dominant,
recessive or degree of freedom coding of the genetic covariate while assuming
a true dominant, recessive or additive genetic effect. In addition, power and
sample size calculations can be performed for gene by environment interactions.
These methods are extensions of Gauderman (2002)