Genetics and human behaviour: the ethical context


Published 01/10/2002

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Research is exploring how genes and the environment influence behavioural traits such as aggression, anxiety, intelligence and sexual orientation.
Fetal scan

If we can identify which genes influence behaviour, it may be possible to use this information to modify people’s behaviour, by developing a range of approaches or treatment.

How might behavioural traits be changed?

  • Genetic interventions: gene therapy – the repair or replacement of a gene, or the introduction of a working gene along aside a faulty one – could be used to alter behaviour.
  • Medical interventions: using medicines to alter behaviour, for example, anti-depressant drugs or drugs to reduce shyness or enhance memory.
  • Environmental interventions: using social policies, such as changes in diet, education or parental care. This type of approach is used already, for example, improving a child’s diet and standard of living can improve his or her intelligence.

It is not obvious which of these approaches will be most effective in altering behaviour, and each case should be considered separately. Although we often assume that environmental approaches will be safe and reversible, this is not necessarily true.

How should we evaluate interventions to change behaviours?

There are five questions to consider when deciding whether it is acceptable to try to change a behavioural trait. These apply to all types of intervention:

  • Will it be effective?
  • Is it safe?
  • Is it reversible?
  • Who makes the choice?
  • What are the implications for individuality?

Should gene therapy be allowed?

In the future, gene therapy could be used to alter genes that influence behaviour. There are two types of gene therapy: somatic gene therapy which modifies the DNA in the body, usually in targeted cells, and germline gene therapy where the reproductive cells are altered and the changes are transmitted to future generations.

We conclude

Behavioural variation within the normal range is not life-threatening and does not have serious implications for health. We consider that gene therapy to change normal behavioural traits is currently too risky, but we recommend that GTAC (Gene Therapy Advisory Committee) should develop guidelines for research into gene therapy for such traits. We do not think that germline gene therapy for behavioural traits within the normal range can be justified.

Is an intervention accessible to everyone?

Who should be able to make use of genetic tests and interventions? Who should pay the costs? There are concerns that only wealthy people might be able to afford interventions, which could exacerbate social inequalities. Public provision of new tests and interventions could require significant resources. How can we ensure that equality is encouraged? One option would be to ban a procedure or intervention entirely so that no one has access to it. Another would be to try to ensure that the intervention is available as widely as possible.

We conclude

We believe that equality of opportunity is crucial. There are particular concerns if a society is divided into groups that are likely to increase inequalities across generations. We recommend that any genetic interventions should be evaluated with this in mind.

How should tests be regulated?

In the UK there is currently no specific legislation that would regulate genetic tests for behavioural traits. It is crucial to ensure there are safeguards for consumers because these tests touch on sensitive areas of personal vulnerability. There is also potential for exploitation, and it is therefore important to ensure privacy and confidentiality.

We conclude

We recommend that genetic tests for behavioural traits need stringent regulation and monitoring. It is particularly important to assess whether tests, and associated interventions, are reliable, accurate and effective. We encourage the Human Genetics Commission (HGC) to give thorough consideration to the issues raised.


One concern is that research in behavioural genetics might exacerbate the trend towards ‘medicalisation’, where behaviour previously thought to be normal is increasingly thought of as a disorder. This development could lead to people being put under increasing commercial and social pressure to use medical interventions, when they are not always necessary. It may also lead to reduced tolerance of different behavioural traits.

We conclude

It is important that genetic or medical interventions are not routinely adopted without adequate consideration being given to environmental approaches. We recommend that health service providers should ensure that the deliberate prescribing of medicines for behavioural traits within the normal range be monitored and, if necessary, controlled.