TGFB1 and pulmonary arterial hypertension: Research indicates that TGF-β signaling can affect X chromosome inactivation in women, contributing to an imbalance in TGF-β signaling in PAH.99 Exposure to hyperoxia resulted in more pronounced EndMT in human PMVECs from male donors compared to those from female donors.95 Likewise, male mice showed a greater susceptibility to neonatal hypoxia-PH in animal models.95