When we know what exactly causes Coeliac disease & the Genes involved, why’s there difficulty in finding a cure?


When we know what exactly causes Coeliac disease & the Genes involved, why’s there difficulty in finding a cure?

In: Biology

My half educated guess on the matter would be that because it is genetic it is hard. It’s one thing to cure a virus infection, it’s another to alter your own DNA. Maybe when CRISPR becomes a commercially available and successful way to alter one’s DNA, we could get cures/treatments for such diseases.

Because just knowing the cause of something doesn’t mean you know the solution. Genes don’t work like they do in the movies. You can’t just inject someone with a green fluid and change their genes. For all intents and purposes, genes are immutable. All that can be done is treat the symptoms, which means finding a drug that can intercept the proteins produced by the faulty genes and prevent them functioning, and that’s much easier said than done.

If you’re actually celiac it’s because you’ve eaten gluten for so long and shouldn’t have been so the inflammation response in your intestines scars the intestinal lining. Healthy intestinal lining has bristles like a brush if you have celiac the lining becomes smooth. So there’s no curing it only preventing.

The answer is that we actually don’t know exactly what causes Coeliac disease.

We have identified two [genetic changes](https://www.acpjournals.org/doi/10.7326/0003-4819-147-5-200709040-00003) that are strongly associated with Coeliac disease – 95% of Coeliac sufferers have these changes. But about 20% of people who don’t have Coeliac disease also have the same changes. So the genes themselves are not enough to cause the disease.

Furthermore, even if we were 100% sure it was only these genes that were causing the problem, we wouldn’t necessarily know *why*. The gene we’ve identified is instructions for how to make a specific cellular machine – ie. a protein. We have a good idea of what this protein does when it’s working correctly. It’s made in immune cells, and is part of the system of machines that our immune cells use to identify things that shouldn’t be in our bodies. So it makes sense that a mistake in building these machines would cause problems with that system.

However, we don’t know why the specific mistakes we know about cause these specific problems – or why they cause problems for some people, but not others. Basically, we have a good idea of where the problem is, but not what the problem is. We could try repairing the gene, but gene therapy is very very risky. Getting gene therapy wrong could mean fixing your Coeliac disease, but giving you another genetic problem (or worse, putting you at risk of cancer) in the process. This type of treatment is extremely young. I believe the first gene therapy product of any kind was approved only 4 years ago, and there’s only a handful of treatments on the market.

To top it off we don’t even know if fixing the gene associated with Coeliac disease would actually treat the disease. It’s possible that the gene changes set off Coeliac disease, but aren’t necessary to keep the disease ‘active’. That gene might be like a match for a fire. Once the fire is already lit, removing the match won’t put it out. And understanding how a match causes a fire doesn’t tell you that water will extinguish a fire.