There are at least 6000 to 7000 rare diseases, which, although individually rare (affect one person in every 2000), taken together affect some 20 million European citizens.

Most of them are chronic diseases with a large negative impact in the quality of life of patients. In addition, they represent a considerable burden on health care systems. While very few are well enough understood to be treated effectively, research needed to tackle these diseases is hampered due to their special idiosyncrasy: complex phenotypes, thin distribution of patients (which impairs gathering of enough subjects for suitable studies), isolation and low number of specialized research groups for each specific disease, fragmentation and lack of standardization of available data and material collections.

Moreover, the particularities of rare diseases are a disadvantage to gain funds for research when competing with common diseases, because project selection criteria often include items such as impact on the health care system or statistical power on the analysis. The establishment of multidisciplinary projects that constitute the necessary critical mass of patients, expertise, and/or facilities is thus essential to address these difficulties and maximize the impact of research on rare diseases.

E-Rare partners are confident that this can be better achieved on a trans-national scale. They have therefore joint their forces to lever the national research resources on rare diseases through synergistic cooperation and preparation of joint and strategic activities. E-Rare shall eventually provide for the overcoming of fragmentation and effort multiplication through better and more cooperation, networking and integration of the European research community working on rare diseases.