ngin - Norfolk Genetic Information Network
 
Date:  3 December 2000

GENE  THERAPY  WITHOUT  THE  CAVEATS

The following BBC report of encouraging results from a ‘gene therapy’ experiment with pig tissue contains no caveats.

There is no mention, for example, of the fact that to date, despite hundreds of gene therapy clinical trials in which doctors have tried to introduce genetic modifications to patients’ lungs, nerves, muscles, and other tissues, the results of this high-tech approach have been worse than discouraging, as Dr Richard Nicholson, editor of The Bulletin of Medical Ethics, explains:

“Ten years ago we were being told that gene therapy was the greatest thing since sliced bread. Today its record stands at: Cures: nil.  Deaths: 5.  Major adverse effects: at least a thousand.”  Not surprisingly, some observers have suggested that gene therapy could more accurately be termed “genetic experiments on human subjects”.

In late 1999, gene therapy’s safety record started to come under serious scrutiny following the death of an 18-year-old enrolled in a clinical trial—an 18 year-old who was, according to an editorial in The Lancet, very far from being in desperate need of a high-tech fix to his health problems, having “ornithine decarboxylase deficiency, which is controllable by diet and drugs” (The Lancet, vol 355, January 29, 2000).

In the ensuing revelations that followed on from this scandal, it emerged that although there had been, as Dr Nicholson noted, around a thousand other ‘serious adverse effects’ in gene therapy studies, researchers and doctors had somehow previously failed to report these to the proper regulatory authorities!

A Washington Post article about the death of the youngster—Jesses Gelsigner, who died at the Institute for Human Gene Therapy at the University of Pennsylvania—reported:

“The University of Pennsylvania, where Gelsinger died, is in many ways representative of the new world of gene therapy. It has allied itself with several financially interlinked biotechnology companies. These firms stood to gain financially if the Gelsinger study had proved successful, including one founded by the leading geneticist in that study.”

[’Gene Therapy’s Troubling Crossroads: A Death Raises Questions Of Ethics Profit, Science’ , Washington Post, December 31, 1999]

According to the Washington Post, talk at Penn was increasingly about “patents rather than patients”, and even while Gelsinger was dying, corporate researchers were busy battling the US regulators, NIH, to keep the serious injuries or deaths in their gene therapy studies from becoming public.

There are good reasons, then, for considerable caution about supposed scientific panaceas and ‘breakthroughs’, particularly when genetic technologies are fuelled not only by fashion but by powerful commercial considerations.

Not a hint of any of this, however, gets into the following BBC World Service report.  Equally ignored is the simple fact—and one which one might have thought, of particular relevance to many in a “World Service” audience - that channeling some more resources into the under-funded area of prevention, and into “low-tech” medical treatments, has to make considerably more sense than big investments of public and private monies into gene therapy’s highly invasive high-cost high-risk high-tech “cures”.
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Gene therapy to calm the heart  - 2 December,2000 http://news.bbc.co.uk/hi/english/health/newsid_1048000/1048814.stm

Researchers hope they can reduce the need for pacemakers Abnormal heart rhythms that could trigger a heart attack could be quickly corrected by gene therapy, suggest scientists.

Although the method has only been tested on pig tissue so far, the results are encouraging - and pig animal kingdom.

The research team used a genetically-modified virus to carry the gene into the pig heart, and more specifically, an area of the heart that helps set the pace of its beating.

The gene targeted is responsible for activating the pacemaker when the body senses the heartrate is increasing too much.

The protein the gene makes blocks the effect of adrenalin - a hormone which normally speeds up heartrate as part of the “fight or flight” response.

The scientists fed the virus containing the modified gene into the artery supplying the “pacemaker”, or the atrioventricular node.

When the heart tissue was studied just a week later, the researchers found that many of the pig AV nodes had been “colonized”, with the different gene in place in nearly half their cells.

Less excitable

And this heart tissue proved far less “excitable” when carrying impulses to drive the contractions of the ventricles, the lower chambers of the heart.

This is theory means they were better equipped to deal with sudden acceleration of the beating of the upper chambers, the atria, which can dirupt the heart’s pumping rhythm and cause dangerous arrhythmias.

This effect is similar to that achieved by prescribing beta-blocker drugs, but the research team, from Johns Hopkins University in Baltimore, US, believe that the gene therapy could eventually replace the drugs in some cases and solve the problem without side-effects.

It is believed that it might eventually replace the need for a pacemaker to be fitted, which involves a risky operation and can prove an inconvenient solution.

Dr Eduardo Marban, who led the study, said: “We’ve effectively treated an arrhythmia in a well-tested animal model, using genes delivered by routine catheter methods - no open chests, no contrivances, just simply modifications of existing technology.”
 
 

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