Table 1.

The list of regression models used to model gene–gene interaction for quantitative traits

Models	Equations
LR1	$p=\alpha +{\beta }_1{G}_{\cdot s}+{\beta }_2{G}_{\cdot t}+{\beta }_3{G}_{\cdot s}{G}_{\cdot t}+{\displaystyle \sum {}_v{\gamma }_v{C}_{.v}+\epsilon }$
LR2	$p=\beta G_{\cdot s}{G}_{\cdot t}+\epsilon$
LR3	$p={\beta }_0+{\beta }_1{G}_{\cdot s}+{\beta }_2{G}_{\cdot t}+{\beta }_3{G}_{\cdot s}{G}_{\cdot t}+\epsilon$
LR4	$p=\alpha +{\beta }_{1}G{\text{res}}_{\cdot s}+{\beta }_{2}G{\text{res}}_{\cdot t}+{\beta }_{3}G{\text{res}}_{\cdot s}G{\text{res}}_{\cdot t}+\epsilon$
LR5	$\text{pres}=\alpha +{\beta }_1{G}_{\cdot s}+{\beta }_2{G}_{\cdot t}+{\beta }_3{G}_{\cdot s}{G}_{\cdot t}+\epsilon$
LR6	$\text{pres}=\alpha +{\beta }_{1}G{\text{res}}_{\cdot s}+{\beta }_{2}G{\text{res}}_{\cdot t}+{\beta }_{3}G{\text{res}}_{\cdot s}G{\text{res}}_{\cdot t}+\epsilon$ where $G{\text{res}}_{\cdot t}=G_{\cdot t}-\overline{G_{\cdot t}}-{\displaystyle \sum {}_v{\gamma }_v{C}_{.v}}$ and $\text{pres}=p-\overline{p}-{\displaystyle \sum {}_v{\gamma }_{v}C{.}_v}$