Understanding what happens to genetic messages in myotonic dystrophy

DNA is like an instruction book that tells our cells how to make proteins. Proteins do lots of important jobs to keep our bodies working properly. DNA is kept safe in the centre of the cell, called the nucleus, and it can’t leave.

But the part of the cell that makes proteins is outside the nucleus. To solve this, the cell makes a copy of the DNA called RNA. RNA can leave the nucleus and carry the instructions to where proteins are made.

In myotonic dystrophy, a gene called DMPK is changed. It has extra bits added — this is called an expansion. When the cell makes RNA from this gene, the RNA gets stuck in the nucleus. This stops the cell from working properly. Scientists can even see the stuck RNA as spots in the nucleus under a microscope.

We don’t yet know exactly why the RNA gets stuck. One idea is that the cell adds tags to the RNA that affects how it works – even though the RNA stays the same. This is called epigenetics. It’s a bit like using sticky notes or highlighters in a book: the words stay the same, but the notes change how you read them.

Some genes or proteins in the nucleus might be adding these tags. Scientists are now testing which ones might be causing the RNA to get trapped.

The team want to find out if RNA is tagged in myotonic dystrophy, what causes the tagging and whether this tagging makes the RNA get stuck in the nucleus. To do this, they will:

1) Remove certain genes using molecular scissors (a technique called gene editing) to see if these genes are tagging the RNA or helping it move out of the nucleus.

2) Use microscopes and other tools to see what happens when these genes are removed. They will check if more RNA can leave the nucleus or if the stuck RNA breaks down. Either result could help reduce the build-up of harmful RNA.

3) Create a new method to find RNA tags. This will help scientists study how different genes affect RNA tagging and make future research faster and easier.

To make new treatments, scientists first need to understand what’s going wrong in the body. If RNA tagging is part of the problem in myotonic dystrophy, and scientists can find out what causes it, they can start working on treatments that target these processes.