Genes, Cells and Brains

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As the 20th century ended, there were many predictions about what we might expect from the next century but one particularly resonated with policy-makers across the world. It was the claim that whereas the past century had been characterised by advances in physics - the fridge, washing machine, television, computer, but also the atom bomb - the 21st century would be dominated by developments in biology.

In line with this claim, in 2003 the completion of the Human Genome Project was announced, and with it the boast that soon the new genetic information would lead to miracle cures for everything from cancer to schizophrenia. But this was not the only new development in biology to usher in the new century, another being advances in stem cell research and new technologies to study the brain.

In scores of media articles and books, we were told this was rapidly leading us towards a world of "personalised medicine", where every ailment would soon be identified by its specific genetic signature, and treated with ever greater precision by drugs or gene and stem cell therapies. But it is not only illness the new biology promised to decipher, but human personality itself - whether that means greater intelligence or a tendency to crime.

But is this brave new world all it sounds - or is there a fundamental flaw in the claims that have been put forward? In their new book Hilary and Steven Rose certainly believe so, and they bring a wealth of powerful arguments to bolster their case. In particular they challenge the idea that both illness and personality can be reduced to biology.

A central argument of this book is that many claims about the link between genes and disease are based on a serious misunderstanding of how genes work. And certainly it is hard to read some of the claims made by leading scientists at the start of the genome project and not be shocked by their naivety, or possible dishonesty given the fact that such hype had an important role in raising funds for the project.

So for instance geneticist Walter Gilbert pulled a CD from his pocket while on a fund-raising exercise and announced, "Soon I will be able to say - here is a human being - it's me." Central to this type of claim was the idea that there would only be only one or a few genes associated with most common disorders and that identifying these would quickly lead to new treatments.

Such genes were to be identified by surveying DNA samples of thousands of individuals gathered in so-called "biobanks" and then looking for links between a particular gene variant and the likelihood of suffering from a disease, whether this were diabetes, heart disease, or mental conditions like schizophrenia or bipolar disorder.

Yet as this book points out, analysis of schizophrenics has so far identified no less than 120 different regions of the genome associated with this condition. This has led some scientists to suggest that it is the combined effect of such changes that predispose a person to schizophrenia but it is not clear how this cumulative effect would work in practise.

Even more confusing are the locations of such regions in the genome. A surprising outcome of the genome project was the realisation, firstly that humans only had around 22,000 genes - more than a chicken but less than a grape - and secondly, that such genes occupied only 2 percent of the genome, the rest being apparently of no function, and therefore called "junk" DNA.

But the vast majority of regions associated with common diseases are in these junk areas. So what if anything have we learned that is useful about the genetic basis of disease from such studies? And why does the reality now emerging diverge so much from what was promised?

A central message of this book is that the search for a genetic solution to society's ills has been a failure. The authors locate this failure in what they see as two main flaws in modern biomedicine - its tendency to reduce human biology, behaviour and even society to genetics, and the drive for profit under capitalism that defines the direction of scientific research.

The authors believe these two flaws are especially concentrated is in the study of the brain. They point to the fact that the failure to pinpoint the genetic basis of conditions like schizophrenia or bipolar disorder has not stopped the increasing tendency to medicalise what would once have been considered normal human behaviours.

So increasingly in schools, children who misbehave are classified as having "attention deficit hyperactivity disorder". Despite little scientific evidence to support such a classification, this has not stopped children diagnosed with this condition being treated with drugs like Ritalin, that has worrying side effects and which critics say is basically just a chemical straightjacket
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This medicalisation of human behaviour is according to this book part of another trend, which is the growing dominance of big business in biomedical science. The authors argue that while previously genetic research had been carried out on a small scale, now it is dominated by industrial sized labs and the interests of the giant pharmaceutical companies.

Of course if modern genetics is so flawed, it begs the question of how any money could be made from it in the form of new medical treatments. In fact the authors claim that the failure of the genome project to live up to its predicted potential has merely led to money flowing into other areas such as stem cell research.

This has undoubtedly been a fast-moving area over the last few years. Previously only embryonic stem cells were thought able to turn into any cell in the body, but ethical and technical challenges have limited their use as a therapy to replace diseased or damaged tissues.

But recently ways have been found to turn ordinary skin cells into such "totipotent" stem cells, offering the possibility that they could offer an alternative route for regenerative medicine. Yet as this book highlights, the claims made about the potential of such technologies run the risk of ignoring the very real obstacles that still stand in the way of their therapeutic application.

So if so many faults exist in these key areas of biomedicine, what is the point of such scientific research if its conclusions are so flawed and its practical applications so limited?

Here I must declare some difference of opinion with some of the claims of this book. I can certainly agree with the points made about the limitations of biological reductionism, and the importance of the profit motive in defining the direction of biomedical research.

But I also feel there is a danger of underestimating the very real and exciting advances that have been made in recent years in our understanding of how genes and cells work. A particularly important aspect of science to discuss here is its claim to objectivity.

Steven Rose has recently said that "science is not objective". This seems to me to be a departure from the view of science developed by the classical Marxist tradition.
According to this viewpoint, despite the natural sciences being deeply imbued with the ideology and the priorities of capitalist society, they nevertheless uncover real truths about the natural world. To do otherwise would compromise the technologies that capitalism needs to keep developing to allow it to continue functioning.

In the physical world, identifying the laws of thermodynamics allowed the development of the steam engine and the motor car, while even seemingly esoteric areas of science like quantum mechanics underpin more modern technologies like the television and the computer.

The situation in the biomedical sciences is complicated by the fact that profits can be made in the pharmaceutical industry by selling drugs that, particularly for the treatment of disorders of the mind, may have doubtful efficacy.

But ultimately, if medicine is to advance, it needs to be based upon truth, not illusion. For me, one particularly interesting aspect of genetics currently is how the reductionism of the gene-based view of biology is being challenged by the actual complexity of the genome.

So recent studies have revealed that the 98 percent of the genome written off as "junk" may in fact contain millions of "switches" that play highly important roles in controlling gene activity.

Although this book briefly touches upon this topic it does not really do justice to the scale of the reassessment that is taking place about this part of the genome.

Nor does it mention that many previously unexplained associations between specific disorders and these junk regions, now make a lot more sense in light of this reassignment of function.

There has also been some criticism of studies purporting to show that many different small genetic differences contribute to a particular disease in an individual. Instead there is emerging evidence that each individual may have their own specific genetic difference that makes them highly susceptible to a particular disorder.

These debates matter because they could have major significance for the possible options for treating disease. In fact this personalised approach to diagnosis is already showing some promise for cancer treatment, where pinpointing the specific mutation driving tumour growth looks set to lead to more targeted drug treatments.

Of course such a focus on genetic links must be carefully weighed up against the influence of the environment on the development of a particular disease. This is true both of disorders of the mind but also of heart disease or diabetes, where poor diet and lack of exercise are at least as important in the development of the disease as any genetic link.

However a simple rejection of all genetic insights as inherently flawed carries with it the risk of turning ones back on potentially exciting new ways to treat disease. The same applies to stem cell research, which although it may be over-hyped in terms of the possibility of therapeutic application in the here and now, still represents a potentially valuable area for future medicine.

This is not just an academic debate but one of some practical importance. For if personalised medicine really is a scientific possibility, this must surely affect the sort of demands activists put forward in society. Personally I am excited by the prospects of new therapies based on genetic insights, but making sure these are not only available for the rich will necessarily be bound up with fighting to preserve, and extend, a health system that is free to all who need it.

Despite my disagreements with some of the arguments put forward by the authors, overall this is an excellent book, both in its critique of reductionism and what it shows us about the distorting effects of capitalism upon biology and its medical applications.

Genes, Cells and Brains by Hilary Rose and Steven Rose, 12.99
Available from Bookmarks bookshop, 1 Bloomsbury Street, London WC1B 3QE, 020 7637 1848.