Cna has been studied as an S. aureus virulence-determining factor, and previous studies comparing wild-type and cna-positive mutant strains have demonstrated that cna-positive strains cause considerably more septic arthritis symptoms in a mouse model and outnumber the mutant strain 24 h after inoculation in a rat model of infective endocarditis [18]. The gene discussed is PPP3CA; the disease is infective endocarditis.