Number of genotyped sibling families (0-10000000):

Alpha level (0-1):

Decreaser allele frequency (0-1):

Maternal Genetic Effect - proportion of variance explained (0-1):

Offspring Genetic Effect - proportion of variance explained (0-1):

Maternal and Offspring Genetic Effect is in opposite direction

Residual covariance between sibling pairs (-1-1):

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

NCP of test to detect maternal genetic effect:

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

NCP of test to detect offspring genetic effect:

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

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

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

If you have an offspring effect size estimate and allele frequency for the genetic variant of interest, you can calculate the proportion of variance in the trait in males explained as (4*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.

Male siblings cannot be used to detect paternal genetic 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