As with many diseases, a genetic predisposition to pulmonary hypertension (PH) is possible in some people due to mutations that are inherited from parents. This can increase a carrier’s likelihood of developing the disease, although it is not a given.

Research has shown that mutations in a gene called bone morphogenetic protein receptor 2 (BMPR2) can cause pulmonary arterial hypertension (PAH), and is estimated to be responsible for 75 percent of familial PH cases. (The World Health Organization, or WHO, divides PH into five groups based on its cause; group 1 covers PAH, which includes inherited PH forms.)

It is believed that low levels of BMPR2, caused by a mutation, can promote cell division (proliferation) or prevent cell death. Both result in an abnormal increase in cells within the small arteries of the lungs, causing a narrowing of the vessel lumen, the central hole of the artery. This effectively decreases the diameter of blood vessels, which causes blood flow resistance, since the same volume of blood is passing through a smaller space. Blood pressure in the right ventricle of the heart and the pulmonary artery increases to accommodate the resistance to flow. 

BMPR2 is inherited in an autosomal dominant pattern. We have two copies of every gene, one inherited from our mother and the other from our father. If a mutation is autosomal dominant, inheriting one mutated copy of the gene from either one of our parents predisposes us to develop PAH, even if the other copy of the gene is normal.

However, many people with a mutated BMPR2 gene never develop PAH; indeed, only around 20 percent of those known to possess a mutated copy develop the condition. The risk for developing familial PAH is higher in women (at 42 percent) compared to men (at 14 percent), suggesting there are other factors involved in the development of the disease. 

Recent advances in research techniques have made it possible to detect rare mutations associated with PAH, and two genes (CAV1 and KCNK3) have been identified as potential causes of rarer cases of familial PAH.

Read about Pulmonary Hypertension Prognosis.

Note: Pulmonary Hypertension News is strictly a news and information website about the disease. It does not provide medical advice, diagnosis or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.