Naked Science Forum

On the Lighter Side => New Theories => Topic started by: Nizzle on 18/08/2009 11:03:47

Title: Gene therapy to cure ALL genetic disorders/diseases
Post by: Nizzle on 18/08/2009 11:03:47
Hi,

I'd like to theorize about a standard model for gene therapy.
Basically, we'd want an effective delivery system for the therapeutic genes.
It has to be able to target specific cells only, insert the therapeutic gene and make sure it's active, and then disappear.
I'm thinking here about a virus, and all the properties it should have.

I'd start with an adenovirus, which has the possibility of inserting DNA in the host's genome.
I'd engineer it so that the virus only has the following components:

1. The original genes and sequences of the virus, except the genes responsible for making us sick.
2. The therapeutic gene between a suitable promotor (the same promoter as found in the genome in front of the defect gene) and a weak stop codon, flanked by a highly selective junk DNA sequence, in order to insert the therapeutic gene + promotor in a region of the genome that is otherwise not used.
3. Excision genes that recognize and excise the replicating genes of the adenovirus, with a promotor that can be activated by a specific drug (let's say Compound X).
4. Genes that code for receptor molecules, specifically to bind on the targeted cells of the host.
5. Some of the hosts HLA coding genes, so the host does not attack the virus by itself
6. Rifampicin sensitive DDRP (DNA-dependent RNA Polymerase) to kill the virus with a Rifampicin treatment after it has done it's job.

The way it would work then is as followed:
A patient with a genetic defect/disease/disorder would be given the adenovirus. Because of the host's HLA genes, it will be regarded as part of the body and not attacked. The virus will recognize and bind with the cells that carry the defect gene (example: muscle cells for stephen hawking's ALS disorder). There it will insert in the DNA, and start transcribing the therapeutic gene. It will also replicate because the stop codon after the therapeutic gene is a weak one.
After some time, a certain % of all host cells will be infected with the virus. (to be determined empirically)
Then the patient will be given Compound X, which triggers the excising genes that will eventually remove the viral DNA from the genome but leave the therapeutic gene intact in the host's genome. This makes sure no new viruses will be made in the body.
The patient will also receive Rifampicin to eliminate reproduction of any already transcribed viral RNA still present in the body.



Any comments?
Title: Gene therapy to cure ALL genetic disorders/diseases
Post by: lyner on 19/08/2009 09:27:45
It just needs to be implimented in a way that actually works. There may be one or more steps in your proposal that are just not viable. Each link needs to work and work safely.
Title: Gene therapy to cure ALL genetic disorders/diseases
Post by: Nizzle on 19/08/2009 11:00:25
Yep, and i did some digging and it seems there are already some clinical trials that explore what I've described in the OP, so my theory isn't really "new" after all

One of those trials aimed at curing muscular dystrophy, but the viral agent caused leukemia in the subjects...
Title: Gene therapy to cure ALL genetic disorders/diseases
Post by: lyner on 19/08/2009 11:12:00
Let's hope it works then.
(And no idea is ever truly new. Don't feel bad).