NOTCH3 and pulmonary arterial hypertension: It is important to remark that, as far as we know, there is no previous evidence of segregation of variants in BMPR2 and NOTCH3, and this fact, might explain in part, why penetrance of BMPR2 in idiopathic cases of PAH is only about 20% (14% in males and 42% in females) [6,13].