Are genetic markers helpful in understanding psychological disorders?
By Sandy Starr (Communications Officer at the Progress Educational Trust)
This article forms part of a School Resource Pack created by the Progress Educational Trust (PET) as part of its project Spectrum of Opinion: Genes. The article incorporates links to an accompanying Glossary of terms, and is followed by a list of 10 key words, phrases and names and a set of Questions to consider. A more extensive version of the article can be found on PET's BioNews website.
The debate 'Marked for Life: Are Genetic Markers Helpful in Understanding Psychological Disorders?' was organised jointly by the Progress Educational Trust and the Royal Society of Medicine on the evening of 3 March 2010. The debate was chaired by Dr Anand Saggar (President of the Royal Society of Medicine's Medical Genetics Section). The debate focused on five neurodevelopmental disorders: autism, attention-deficit hyperactivity disorder, bipolar disorder, major depressive disorder and schizophrenia.
These five disorders are currently being studied by the Psychiatric Genome-Wide Association Study Consortium , which describes its work as 'the largest biological experiment ever conducted in psychiatry'. One of the coordinators of the the Psychiatric Genome-Wide Association Study Consortium is Nick Craddock (Professor of Psychiatry at Cardiff University), who was the first speaker at the debate.
Professor Craddock began by saying that our understanding of what causesmental illness is relatively poor, and that diagnoses of mental illness are generally not made using laboratorytests, but instead by observing complexsymptoms and signs in clinics. How can we improve diagnosis and treatment?
Professor Craddock went on to explain that there is often a clear relationship between someone's risk of developing a neurodevelopmental disorder, and the existence of the disorder in other members of their family. Because of the way that this risk increases, if the family member with the disorder happens to be your identical twin, we can be confident that genes are involved in the way these disorders are inherited. But developing such a disorder remains a risk rather than an absolute certainty, even if it is your identical twin who has the disorder. This tells us that genetics cannot be the only explanation.
The second speaker was Derek Bolton (Professor of Philosophy and Psychopathology at King's College London). He explained that most research into mental health has only discovered combinations of genes responsible for small effects. Although many areas of science and medicine have become clearer as our understanding of them improves, Professor Bolton was worried that mental health might remain difficult to understand, if the complex genetics mean that 'nature does not oblige'.
New treatments could still emerge from genetic research into mental health. One example discussed by Professor Bolton was the area of psychopharmacogenetics, where medication might be developed that targets individuals with particular genetic variants. He also discussed environmentalintervention, where changes of lifestyle and circumstance might be recommended to help with mental illness. Or we might develop new genetic and environmental profiling options, so that people at risk of psychiatric illness can be better identified and helped at an earlier stage.
The third speaker was Fenno Outen (Head Occupational Therapist for Newham at East London NHS Foundation Trust). He began by asking how the genetics of mental health relates to culture. According to Mr Outen, some problems - for example, 'work-related stress' - can be created through culture (rather than through biology), but then go on to have a negative impact on people's mental health. This is because once a person believes themselves to be suffering from a problem, this alone can sometimes be enough to make the problem become real.
Mr Outen went on to discuss the idea that mental health problems are biopsychosocial, meaning that their causes and consequences are biological, psychological and social all at the same time. People sometimes call this idea the 'biopsychosocial model', but Mr Outen argued that this is 'cheeky', because models are supposed to improve our understanding of things rather than just describing possibilities.
A comment was made by audience member Larry Arnold, an academic and disability rights campaigner who himself has a diagnosis of Asperger's syndrome. He questioned the nosology used by people conducting research into mental health. According to Mr Arnold, if research into mental health begins with an incorrect classification of disorders, then no matter how much effort and funding goes into the research, the results it produces will not be very useful.
The debate finished with the three speakers offering different views on how helpful genetic research will be for people with mental health problems. Professor Craddock was optimistic, and said that genetic research will be very helpful in future. Professor Bolton was more pessimistic, and said that the genetics of mental health may be too complex to be helpful. Mr Outen said that more research will be needed, before it is possible to say one way or the other how helpful it might be.
10 key words, phrases and names
Is there a difference between the accuracy of a diagnosis involving a test in a laboratory, and the accuracy of a diagnosis involving observations in a clinic?
Can a mental health problem have no biological cause at all? If so, then how might such a problem be treated?
Is it possible to tell whether a disorder has been correctly or incorrectly classified, before understanding what causes it?