Figure 2.

E-nose measurement of urine from H2-different mice. Scores plot of a PCA. The x axis shows principal odor component 1; the y axis shows principal component 2 (arbitrary units). Each dot represents a pool of urine from five [BALB/c (H2^d) and BALB.B (H2^b)] or six [C3H (H2^k)] male mice collected during 3 nights. Two samples from each pool were analyzed; the two dots representing one pool are marked by an ellipse.