Treating Genetics

Chaperone Medication

Some diseases, mutations cause proteins to misfold and get stuck, this helps them unfold and get unstuck

Enzyme Replacement Therapy

Instead of fixing the underlying mutation, we give the patient the protein they can’t make themselves

Transplanted organs

Instead of fixing the underlying mutation, we replace the affected organ with a donor organ from an unaffected person

Gene Therapy

Don’t fix the mutation, but instead insert a new working copy of the gene from elsewhere in the genome

Genome editing

We use CRISPER-Cas9 to make a change in the genome

Techniques for altering DNA

In vitro and in vivo

In Vitro

Remove stem cells, edit them, allow them to reproduce in a test tube or dish, and then put them back in the patient

In vivo

We inject the patient with viruses that have been altered to allow gene editing components to enter cells and change DNA

Why do we use viruses as vectors

1. They have mechanisms to sneak past cell defenses and get inside

2. They have mechanisms to insert their own genome into the host cell’s DNA

How does CRISPER-Cas9 force the cell to repair DNA

1. The cell uses an error-prone method to fix it badly, adding or deleting bases in the process. Can cause frameshift mutations that break the gene.

2. The cells uses other sequences in the guide RNA as a template (DNA guide) to fix the DNA. The guide RNA contains the edit we want to make

Ethical Issues with altering DNA

1. CRISPER isn’t perfect

2. Using viruses to insert new genes randomly may disrupt a needed gene or increase cancer risk

3. Price/access

4. Which genes should be altered

5. Should we make edits heritable