The Norwegian National Advisory Unit on Rare Diseases defines as rare diseases diagnoses that occur in fewer than approximately 2700 individuals or 1 per 2000 inhabitants in Norway.
In Norway, a diagnosis is considered rare when fewer than 1 in 2000 people have the diagnosis. This is how it is calculated in most of Europe and the rest of the world.
We do not have good figures on how many people in Norway have a rare diagnosis. By definition, this means that fewer than about 2,700 people will have one diagnosis in Norway. However, based on the current definition, it is assumed to be between 190,000 and 320,000 people.
Based on the definition of a rare diagnosis (1 in 2,000), we estimate that there are around 7,000 different diagnoses that are rare. A change in the genes causes about 80% of these diagnoses.
Read more about rare diseases here: