Table 2.

Results from separate PCA and PLS analyses by gene, level of expression, and developmental stage

Gene expression	Developmental stage	Total variation	Limb/gene	A-P
			RV	RV
High Hoxa11	E10:11–E10:22	0.026	0.83	0.51
	E10:23–E11:10	0.005	0.89	0.71
	E11:11–E11:22	0.009	0.67	0.64
	E11:23–E12:10	0.005	0.73	0.87
Moderate Hoxa11	E10:11–E10:22	0.018	0.78	0.61
	E10:23–E11:10	0.014	0.94	0.90
	E11:11–E11:22	0.020	0.86	0.83
	E11:23–E12:10	0.011	0.77	0.79
High Hoxa13	E10:11–E10:22	0.025	0.88	0.72
	E10:23–E11:10	0.019	0.94	0.84
	E11:11–E11:22	0.008	0.95	0.88
Moderate Hoxa13	E10:11–E10:22	0.018	0.88	0.77
	E10:23–E11:10	0.018	0.92	0.88
	E11:11–E11:22	0.012	0.93	0.89

Note: Total amount of shape variation within each subsample is provided as the sum of the eigenvalues of the corresponding PCA. PLS analyses were performed after a single Procrustes superimposition in which the landmarks from the two subsets were fitted simultaneously and thus the relative size and position of the two blocks were considered in the analyses as integration factors. PLS results are provided as RV coefficients computed for both sets of a priori defined modules (Limb/Gene and Anterior/Posterior limb regions). RV coefficients can range from 0 (i.e., complete independence) to 1 (i.e., total interdependence between blocks).