Transgenic studies showed that P2X1 receptors on platelets do not contribute to normal bleeding but play a significant role in thromboembolism models (P2X1 reduction was protective (Hechler et al., 2003) and over-expression of P2X1 receptors increased mortality (Oury et al., 2003)). Here, P2RX1 is linked to Thromboembolism.