This is probably the most international meeting of CFers in a while.
More and more mutations and especially mutation combinations that are being discovered in the people who are suspected of having CF. The standard for CF is still claiming that 2 identical mutations are required to be affected a person. This was when most people suspected of having CF mostly Did have two identical mutations. Now polymorphisms (5T, 7T, 9T and TG's for example) are getting the status of a mutation.
Still, CF is a rare disease with a world population of of ~70,000, 73% of which share 5 mutation sets. There's around 3000 known CFTR mutations shared with the ~19,000 people. If they were evenly distributed, only six people would share a mutation set. It gets worse, we now know that combinations are virulent in many cases. This is 4.5 million combinations, far more than the highest estimate of the world CF population. My mutation, S1235R has one person in the CFTR2 Database and it's not virulent and it isn't me. Fortunately I was tested using the sweat chloride test and confirmed with CF before any genetic testing.
After my genetic testing came in I saw my CF specialist. I had met him once before, when the genetic testing was ordered. At the appointment where we discussed the results of my genetic testing, the first words out of his mouth were "so, you're a carrier". Ordinarily, this news would be crushing, after fifty years I have a diagnosis and you are going to take it back? I'm a geneticist and if I know anything about genetics, I know that certainty is very rare.
The CF diagnosis wasn't on anybody's radar including a host of specialists. Don't be too hard on your doctors, the only reason my diagnosis was at a CF center in Boston and not Denver was because the tiniest bit of calcification had shown in my pancreas. This tiny clue got my wife going and we found one of about 4 Pancreatologists in the U.S. After being given a Pancreatic function test and being told it was a record for bad, I was sent the Boston Children's Hospital for a sweat chloride test.
I have two points to make. If you or your child shows symptoms of CF, being treated like it's CF is most important. A failed sweat test does not rule out CF, and neither should genetic testing, and treatment is going to be the same with the exception of the current genetic drugs. If it looks like a duck, quacks like a duck and walks like a duck, treat it like a duck. Think about all the people who were diagnosed with CF before 1989 when we decoded the CFTR and identified a few mutations. Some have no CF mutations, some are symptomatic carriers, and the majority are genetically a CFer. Twin studies have established that two CFers, genetically diagnosed, may have wildly different health issues. I spent some time messaging with siblings, actually just the sibling that doesn't have any CF issues. Her younger brother was ravaged by the disease.
The other point, as much as we would like to hear about the issues caused by our mutations by comparing notes with others who do share them, it's not something you can rely on in most cases. Some general trends can be inferred if you have a mutation set that has maybe a dozen registered people with your mutations and some other mutation or both of your mutations if you are lucky. The whole reason for the CFTR and CFTR2 Databases is a resource for inputting your mutations and see what other people who have registered experience as a trend. Google CFTR2 Database and it will take you there.
Just remember, CF has an extreme range of symptoms with genetically CF patients being denied a diagnosis because they aren't sick to carriers that require a transplant. Chances are that he would be much worse if his CF was going to be severe. There could be a development of respiratory issues with time but it too is wildly variable.
Keep up with CFTR2 and over time it will become reliable as numbers increase.
LL