Fig. 2
From: Codon usage of host-specific P genotypes (VP4) in group A rotavirus
Principal component analysis (PCA) of VP4 coding sequences for eight RVA P genotypes. The eight P genotypes were classified into three groups by hosts: human, porcine and zoonotic groups. X and Y axis represented principal component 1 and principal component 2, respectively. The dots represented VP4 sequences. The ellipses in the figure predicted new observations with a probability of 0.95. New observations from the same group were expected to fall inside the ellipses