Rare diseases affect a very small number of people in the population.

It is estimated that in the world there are about 300 million people living with some of these pathologies. In Europe we speak of a rare disease when it affects 1 person in every 2,000. This means that a disease may be rare in one region, but common in another.

At present, some 7000 rare diseases have been described, many of them are genetic, but not all. They usually appear in childhood (eg. osteogenesis imperfecta, Rett syndrome …) although there are also some that begin to manifest in adulthood (eg. Huntington’s disease, amyotrophic lateral sclerosis …).

Rare diseases pose many challenges, both diagnostic (take an average of 5 years to diagnose) and therapeutic (many of them lack effective treatment).

Patients and relatives often have to run into difficulties derived from the lack of information about their disease and the lack of knowledge on the part of the specialists who treat them. However, there are reasons for hope, since there are many advances in this aspect and more and more are known in that they open the door to the implementation of new therapeutic routes …

There is no cure for many of them, but a diagnosis helps the family not only to be able to benefit from social assistance but also to alleviate the psychological stress caused by this lack of diagnosis and the misunderstanding to which they are led by society.


Genetic tests can help to achieve early diagnoses that allow for early treatments, and therefore, are more effective.

If you want more information about genetic studies for the diagnosis of Rare diseases