where β0 is the intercept, and β1, β2, and β3 represent the regression coefficients of their respective terms. As before, the parameter “sex*gene” is only retained if it significantly improves the fit of the model. The p-value threshold for significant correlation is calculated by an F test, which compares the appropriate model (Equation 7 or 8) to the null model (Equation 9). As before, multiple testing was addressed with use of the FDR, ranking the p-values obtained from the above F tests and setting α = 0.01.