Fig. (3) Multivariate statistics on CYP1A kinetics with steroid substrates. (A) Hierarchical classification performed on steroid activities using the average linkage method and Ward's approach. (B) MDS configuration of steroid activities using the absolute MDS model (calculated Kruskal's stress = 0.063). (C) PCA for steroid activities, the two first principal components retain 78.9 % of initial variance in original data (PC1 retains 60.1 %). Solid circles represent 1A2s; grey points, 1A1s; and grey triangles, 1ACh4 chimera which is mostly of mouse 1A1 sequence [Ref = 60]. The PCA plot shows data means, and the helices represent data dispersion for each CYP1A enzyme.