Gene Therapy

Imagine you suffer from Cystic Fibrosis, the most common genetic disorder found in Caucasians. CF causes your lungs to fill with mucus- making breathing increasingly difficult. There is no way to stop this from happening because the disease is genetic. A person with CF either lacks, or has a slightly mutated version of the piece of chromosome required to create a specific amino acid- used to break down that mucusy build up in their lungs. However gene therapy can fix it. First a sample of DNA is taken and sequenced. the strand of code containing the CF gene is then spliced and a healthy version of the gene is inserted into the strand. Then this healthy strand of DNA is put into an inert virus (similar to how a flu-shot works), and the virus is cloned. With CF the patient then simply breathes in this viral vector and the virus goes to work inserting the healthy DNA into the corrupt lung cells still carrying the CF DNA. Within a short period of time the virus has spread the healthy DNA throughout the lungs and proper amino acids begin to be produced. This is the potential of gene therapy, suffers of genetic disorders can be cured from their deliberating illnesses. -Response to point (1): I agree with my opponent on one small bit- that the current form of adult gene therapy is a relatively unstable process, involving some live risks. However I need to point out several key things. Firstly that the technology is in its infancy still- and as with any medical procedure the early techniques faced numerous problems. When heart transplants were first being performed in the late 60's a majority of the patients tended to die within the first 30 days. With the advancement of technology and technique some clinics like that of NZTI have had over a year of 100% success with heart transplants: http://www.integris-health.com... The same could be said for gene therapy. the Human Genome project (HGP) finished mapping the human genome in 2002- now the human Genome Diversity Project has got underway- with this they are attempting to realize the medical and social potential of the information learned from the HGP. Before the HGP only a handful of diseases were understood in terms of genetics (Cystic Fibrosis being one)- Since the HGP has bore fruit scientists have recognized over 500 genetic diseases, and the whereabouts of each of them. The diversity project will hopefully bring medical science into the fold and new technology and techniques will hopefully come to light. This means that gene-therapy is about to get a huge upgrade, and stands to become a hugely viable solution for people suffering from genetic dysfunction. Also as for the current method of doing gene therapy, almost all viruses used for vectors are inert (no bacteria is used at-all, it is done with viral vectors- i point this out because you flop between saying virus and disease, large difference). The reason viral vectors are as follows: * Safety: Although viral vectors are occasionally created from pathogenic viruses, they are modified in such a way as to minimize the risk of handling them. This usually involves the deletion of a part of the viral genome critical for viral replication. Such a virus can efficiently infect cells but, once the infection has taken place, requires a helper virus to provide the missing proteins for production of new virions. * Low toxicity: The viral vector should have a minimal effect on the physiology of the cell it infects. * Stability: Some viruses are genetically unstable and can rapidly rearrange their genomes. This is detrimental to predictability and reproducibility of the work conducted using a viral vector and is avoided in their design. * Cell type specificity: Most viral vectors are engineered to infect as wide a range of cell types as possible. However, sometimes the opposite is preferred. The viral receptor can be modified to target the virus to a specific kind of cell. - http://en.wikipedia.org... As the list points out viral vectors are used for gene therapy because they are safe. You claimed that viral vectors could spread HIV/AIDS virus. This is impossible because the AIDS portion is removed and replaced with the healthy DNA the patient requires. On your note about embryos- they need not be exposed to viral vectors at-all. To remove a genetic disease from an embryo we can simply either pick one that doesn't have a disease, or splice out the corrupted parts and splice in healthy ones in their place. -Response to (2): As stated above in time the technology involved in gene therapy will advance. These advancements will make gene therapy more and more cost-effective and also a more viable solution. I agree that if we abuse the technology it could be used by people in positions of advantage to further inequalities. However this is a nightmare situation- only possible in the United States. I'm in Canada where "socialized medicine" is the way, if something like gene therapy became available it would be available to everyone equally- not just elites, same as in Britain, France, China, India, Germany, Australia, Ireland, Finland, Sweden, Netherlands, Singapore, Thailand, Cuba, and more. Health care for the rich is truly an home-grown American experience which has far bigger problems than gene therapy to deal with. As for third-world being left-behind, this is a slightly more possible problem. the major solution to such inequality would be an international effort, like what has been done with mumps, polio, whooping cough, small-pox- and with diseases that are currently being removed like malaria and guinea worm. There is no reason to believe that an medical team (doctors without borders, the red cross, ect...) couldn't go in and treat genetic diseases in the third world with safe and effective viral vectors. You also mentioned Jewish groups attempting to stop Tay-Sachs (one of the most horrible and painful diseases ever- the infant lives in extreme pain until the age of 3). If gene therapy had been available that instance of eugenics performed by the Jewish community could have been averted completely. You also mention the possibility of groups attempting to promote of remove a behavioral trait like homosexuality. This is an impossible scenario. First because behavior is linked heavily with environment- little of it is from genes (this is not nature vs. nurture- these are the facts): "Despite publicized claims, no genetic variant has been shown conclusively to influence any of these (behaviour, sexual-orientation)" (Dr. Bob Hepple). "Genes are very poor predictors of behaviour because behaviour is complex" (Dr Helen Wallace). -sorry i lost the links.... -Response to point (3): The problem you suggest in point 3 is a more social oriented view of what was suggested in point 2- abuse of gene therapy. Thus I promote my previous defense of why abuse is unlikely and limited. Also, what is wrong with society placing a high value on the eradication of genetic disease? -Response to point (4): Perhaps when America has finally destroyed the atmosphere and earth is a toxic hell- people with Cystic Fibrosis will be the only people able to breathe. I apologize for the crude humor- anyways genetic diseases pose a threat right now- if we really believed that stopping disease whether through vaccination, surgery, gene therapy, anti-biotics, ect, would create a huge risk for the inception of new problems we would not bother curing cancer or AIDS. gene therapy in specific does not weaken the immune system as to promote disease susceptibility- all that is occurring is corrupt DNA is being replaced with healthy and properly operating versions of it. Although it is good to think about long-term consequences- being Nostradamus gets us nowhere. -Shoot....it appears that i've ran out of word space.....I look forward to my opponents' response and the debate in the next round