It may seem unbelievable that there is an area of unexplored medicine, as it turns out that it is so, there is an unofficial specialty that has many patients to cover, it is rare diseases. Doctors along their way as a student, prepare for the management of many diseases that afflict the human being, some more common than others, and during the specialty they focus on a certain organ and system to be treated, so the Knowledge is more specific. What is a rare disease? It is the term that groups all those diseases that occur in a very small number of people within a population. From the legal point of view each country has its definition, the truth is that they are pathologies whose occurrence is much lower than the known minimum of known pathologies, such as hypertension or cancer, for example. Why is there no specialist in rare diseases? It turns out that rare diseases are very diverse and strange, there are some that are not even described in the medical book’s others have been underdiagnosed, knowing clearly, just a few years ago, all this makes integration a bit more complex in a single specialty that treats them all Who covers that space today? The answer is: No one and everyone, yes. It turns out that there are centers for the treatment of rare diseases throughout the world, but there is no specialist for this (curious, right?) Who work in this area are internists with studies and knowledge on certain diseases, in turn there are geneticists, and many other specialists who make use of the knowledge of their specialty plus that of the disease, try to find answers for patients and for medical science in general. How much population is affected by rare diseases? Due to their incidence and prevalence it is a bit difficult to estimate, but it is known that they are diseases that affect sows of 6 to 8% of the world population, this means that they affect millions of people. The causes are usually linked in a high percentage to genetics, so future specialists in rare diseases should have a deep knowledge about genetics, their variations and their expressions in the human body. These are 5 rare diseases that you probably didn't know about Moebius syndrome Brugada syndrome Marfan syndrome Prader Willis syndrome Tourette syndrome More than 100 rare diseases are known, and many more are suspected, rare diseases not only lack their own medical specialty, but also lack specific and adequate treatments. For medical students and future specialists, recognizing the need for this specialty can make a difference in the lives of millions of people affected by any of these diseases.