GENES & BEHAVIOUR > INFORMATION > SHEET 4

Testing and interventions

	Daniel Greenwood

In Making Astronauts the Proteus Company test Adam and Martin’s embryos for diseases and behavioural traits.

ADAM: Well – out of these ten embryos three were found to possess the gene cluster that can give a higher than average susceptibility to cancer - so those three – the three with cancer- were disregarded – which left seven. Of those seven all possessed to some degree some sort of spread of genes which could indicate intelligence.

While genes for diseases and disorders have been identified, we have not as yet reached a point as in Making Astronauts where genes for behavioural traits have been identified. Some researchers are attempting to locate specific genes, or groups of genes, associated with behavioural traits and to understand the complex relationship between genes and the environment.

If genes that influence particular behavioural traits are identified, it could become possible to test for the presence of variations in these genes in individual people. No such tests currently exist. Moreover, there is disagreement about whether tests that predict human behaviour accurately could ever be developed. But even if genetic tests could not yield predictions of a definite outcome, it may nonetheless be possible that tests that suggest an individual will have an increased chance of possessing a particular trait to a greater or lesser degree might be developed. Such hypothetical tests might be undertaken for a variety of purposes. One purpose would be simply to gain knowledge about the influence of genes on behaviour. Another purpose might be that of intervention, or treatment, for example to prevent aggressive behaviour by using medicines, or by attempts to change relevant aspects of the environment.

A further purpose might be that of selection. This encompasses, for instance, prenatal testing, the streaming of children in schools on the basis of intelligence and aptitude, the screening of employees and jobseekers to exclude those with traits that employers consider undesirable and the use by insurers of genetic information about behaviour and personality traits in order to estimate risk.

Yet another purpose might be to claim diminished legal responsibility for one’s actions or to mitigate punishment for criminal behaviour. This argument has already been put forward in one American trial. Stephen Mobley, on death row for shooting the manager of a pizza parlour, appealed that he was ‘born to kill’ because of genetic factors.

The regulation and monitoring of usage

If genetic tests for behavioural traits, and the means to intervene in the development of an embryo with the genes for those traits (interventions) were developed, we would then need to question who would make use of them? Who would fund the process? If only individuals who could afford to pay for such tests were eligible this could lead to even greater inequalities in society, especially as these techniques would enhance abilities.

We believe that equality of opportunity is a fundamental social value, which is especially damaged where a society is divided into groups that are likely to perpetuate inequalities across generations. We recommend, therefore, that any genetic interventions to enhance traits in the normal range should be evaluated with this consideration in mind.
Genetics and human behaviour;the ethical context
The Nuffield Council on bioethics.

It is essentially important to consider how genetic tests and genetic, medical or environmental interventions may be made available. Consumers may be at risk of exploitation if the process is not carefully regulated and monitored.

On the presumption that tests for genetic influences on behavioural traits in the normal range, of varying quality and predictive power, will become available, we welcome the consideration by the Human Genetics Commission (HGC) of genetic tests supplied directly to the public. We encourage the HGC to give through consideration to the issues raised by genetic tests for behavioural and personality traits. We recommend that both the public and private provisions of such tests, if they are developed, should be stringently monitored and regulated as necessary.
Genetics and human behaviour;the ethical context
The Nuffield Council on bioethics.

How could genes that contribute to variations
in characteristics be tested for?

Molecular genetics looks at identifying differences in genes that contribute to trait variation in characteristics or traits between individuals. Research in molecular genetics tries to identify variation in particular genes that influence behaviour, by examining the DNA of individuals. This is difficult because there are usually many genes involved, each of which may only have a small effect. Many associations between a genetic variant and a behavioural trait have been reported but not successfully repeated. The research does not seem to explain how the gene influences behaviour although researchers state that they will be able to identify how genes influence behaviour.

Research in molecular genetics can also play a role in psychosocial and epidemiological research, enabling confounding genetic effects to be identified and controlled for, and to allow for further study of the non-genetic factors that influence a characteristic. A further reason for undertaking research in normal variation is that it will provide information relevant to disorders and diseases.
Genetics and human behaviour;the ethical context
The Nuffield Council on bioethics.