Power Calculator for Sibling Pairs Without Parental Genotype Information

Power to detect parental genetic effect (1 df test):

        NCP of test to detect parental genetic effect:
        

        Power to detect offspring genetic effect (1 df test):
        

        NCP of test to detect offspring genetic effect:
        

        Power to detect either parental or offspring genetic effect (2 df test):
        

        NCP of test to detect either parental or offspring genetic effect:
        

        

Alpha level is the type 1 error rate for the genetic association study.
Parental genetic effect is the proportion of variance in the trait explained by parental genetic effects at the locus.
Offspring genetic effect is the proportion of variance in the trait explained by offspring genetic effects at the locus.

If you have an effect size estimate and allele frequency for the genetic variant of interest, you can calculate the proportion of variance in the trait explained as (2*P*(1-P)*b^2)/VAR(trait), where P=allele frequency, b=effect size estimate.

Residual covariance between sibling pairs is approximately equal to the sib-pair correlation for loci of small effect.


Parental genetic effects could refer to maternal or paternal effects.


If you use this utility in your research please cite: Hwang D et al. (in preparation) Detecting maternal and paternal genetic effects on offspring phenotypes using imputed parental genotypes



If you encounter any errors please contact the developers at d.evans1@uq.edu.au