Baboon studies could directly assess the role PT has in many aspects of disease pathogenesis, including pertussis-induced coughing, dissemination and colonization of the lungs and upper respiratory tract, systemic dissemination (if any), lung inflammation and damage, pulmonary hypertension, skewing of the host immune response(s), and other systemic perturbations. This evidence concerns the gene F2 and pulmonary arterial hypertension.