A Brief Introduction to Gene Therapy

I haven’t written an article on Gene Therapy, and seeing as it is something a vaguely specialise in, I think it’s about time I do. So here it is.

Gene Therapy is an umbrella term for many types of treatments. Ultimately it involves changing or fixing or replacing genes that are defective or mutated in someone’s cell such that the cells can function again. Remember that genes represent the code by which just about everything that happens in the body follows. It’s like the instruction manual for the body. So if some of that code is missing, or incorrect, the body won’t work properly.

Examples of such diseases would be cystic fibrosis, Huntington’s disease, Sickle-cell anaemia and a huge range of immunity disorders. Even cancer is caused by genetic mutations. So if there was a way to fix the code, repair it in some way, this would have huge benefits to thousands of people.

More here: http://offthemark.com/

One way to fix a broken code involves using viruses. This may sound alarming, but it is actually quite effectively used. The basic principal revolves around using a harmless virus i.e. one that will only infect certain cells and won’t replicate, to carry the corrected gene code to cells. Viruses do this anyway – when they infect a person, they are often actually infecting the cells, their own gene codes being incorporated into the host cell. Usually this is detrimental, but by controlling what gene sequences are included in the virus, you can make tailor what happens when a virus infects a cell.

There are a few ways to ‘infect’ the cells with the virus. Say you have someone who has cystic fibrosis; their lung cells have defective genes that code correct mucous production. So if these genes were fixed, the cells would work correctly. Ideally, the virus could be injected into someone’s lungs, where they would infect the lung cells. These lung cells would ultimately then start performing the way they should. This is termed ‘In Vivo gene transduction’ i.e. you are placing the virus directly into the human, into the cells. Another method is to take the defective cells OUT of the body, and then infect them, only to put the hopefully fixed cells back into the body. This could work for any disorders that involve bone marrow (e.g immunity diseases or blood disorders). This is ‘Ex Vivo gene transduction’.

So there is the introduction to gene therapy. I could write a book on it. But there will be more posts soon... huge inroads are being made all the time in this field.