What is the rarest heriditery disease in the world?

Question

What is the rarest heriditery disease in the world?

Answer 1

There's a whole site of them.

http://www.hon.ch/HONselect/RareDiseases...

Answer 2

There are many so, it would be difficult to choose only one.

HHT ( Osler-Weber-Rendu) .

Any disease that has 3 names to it are considered rare, hereditary or life-threatening. For example; Lou-Gehrigs-Disease

http://www.rarediseases.org/search/rdbli...

simply click onto the disease that you are interested in. They are in alphabetical order.

Answer 3

Infitago?  a skin disease.