Question: What is the rarest medical disease you have researched?

Eleanor Williams answered on 20 May 2020:

The technical definition of a ‘rare disease’ is one that it is found in 1 in 2000 people. I work on a disease called fibrodysplasia ossificans progressiva (or FOP) which is found in 1 in 2 million people – so x1000 rarer than the definition of ‘rare disease’. This makes it ‘ultra rare’. There are about 40 people in the UK with it and less than 800 people world wide.

It’s possible that there may be people who are diagnosed around the world with it (many doctors just don’t know what it is so can’t diagnose it – this is something that a doctor in South Africa for example is trying to counteract – taking information video’s to remote parts of the country to educate on it) so it might be a little less rare than we think but not by much and it still comes into the ‘ultra rare’ catagory.

FOP is a condition where your ‘make bone’ signals are overactive and instead of making normal bone you end up replacing muscles over joints with bone over the course of your life. It’s caused by one mutation in one protein making that one protein slightly oversensitive. We’re trying to find a medicine that will bind to the mutant protein and stop it working – effectively switching it off like a switching off a car with the key. Hopefully that will then stop bone being made in the wrong place at the wrong time. Since it’s only one protein that’s gone wrong, this actually makes it a more solvable challenge because it’s clear where the problem is.