Rare diseases : why bother?

Abstract

Rare diseases are those diseases that affect a small number of people when compared to the general population. In 2009 the EU adopted the definition that a rare disease has a prevalence of less than five persons being affected out of 10 000 persons.1 An important estimation is that 8% of the population is born with, or develops, a rare disorder over their lifetime. Thus, it is estimated that around 30 million Europeans suffer from a rare disease. Based on the same assumption, the Maltese rare disease population should be around 25,000 patients. The EU definition further states that rare diseases are life-threatening or chronically debilitating conditions. About 80% of rare diseases have a genetic origin, being either monogenic or polygenic.