Inherited pulmonary arterial hypertension

Pulmonary hypertension is now a well recognised disease and is no longer regarded as rare. As new therapies come on line, the disease comes into recognition by cardiologists, respirologists, rheumatologists and paediatricians. The genetic basis is also becoming clearer, not only in the idiopathic form, but also in the forms secondary to chromosomal abnormalities, micro-deletions and systemic disease. The present chapter aims to introduce the reader to the genetic and molecular abnormalities in pulmonary hypertension, predominantly pulmonary arterial hypertension (PAH). However it must be realised that the field is now very large, with over 4500 gene mutations recognised to be implicated in pulmonary hypertension. This chapter covers some of the interesting areas in this field, including the genetic changes in idiopathic PAH and the changes seen in association with congenital heart disease. The molecular changes that accompany this gives an insight to the cellular abnormalities in such disease.