Genetic testing for depression creates an ethical minefield

Finding out that you a genetically predisposed to depression can make you feel worse. Lloyd Morgan

A friend of mine is currently undergoing chemotherapy treatment following surgery for breast cancer. Recently, she told me that she would happily pay the AUS$4000 for a genetic test to detect whether she had cancer genes if it meant she didn’t have to complete the course of treatment.

Being her friend (and an ethicist with an interest in genetic testing), I immediately replied that genetic testing is really quite complex. Naturally, she wanted to know more.

Well, in my relatively naive understanding of this area, I promptly explained, a genetic test might not reveal the information she was looking for. It may not find a genetic risk in a person who still develops breast cancer, or it may identify a gene in a person who won’t develop breast cancer.

And I guess if you have a genetic test, you also have to be prepared to learn something other than what you were expecting so you have to consider the consequences of that. What would you do?

But what does my discussion with my friend about genetic testing for breast cancer have to do with the ethical pitfalls of “geneticising” depression? A great deal, in fact.

Since genetic developments began, genetics has been critiqued for the way it can be used to reveal and explain health and disease. As new gene associations with diseases are identified, there is a trend to explain the cause of health and illness by genes, obscuring sociopolitical, cultural and environmental factors.

Scientists are still exploring the genes associated with depression and looking into their interactions with environmental, social and psychological factors, which may increase a person’s susceptibility to developing major depression. But, we must be cautious of the possibility of geneticisation of depression.

Predictive tests for depression based on algorithms are being developed in the United Kingdom and Australian research has found that there’s public interest in undertaking predictive psychiatric testing for major depression.

But there are ethical problems with identifying gene susceptibility to depression. And scientific debate about whether it’s even possible to find a gene associated with depression aside, we know little about what motivates individuals to undertake predictive tests. Or, what the consequences of knowing predictive information are.

An Australian survey of 1544 individuals identified that having a personal history of mental illness (82%), self-estimation of risk (77%), being female and having no post-school education were associated with the intention to undertake predictive tests.

But when people are already suffering from being ill, or the side-effects of medications (like my friend) and other treatments for their illnesses, motivations change. While the side-effects of medical treatments for different conditions are not very comparable, the potential impact of their effect on someone’s decision to undertake a predictive genetic test should not be ignored.

The same survey found that a significant number of the people who thought evidence of a genetic component to depression would affect stigma believed it would increase (72%) rather than decrease (28%). This leads to the first ethical pitfall of geneticising depression – the impact on individual identity, stigma and shame.

While there may be some public benefit in early treatment and prevention, for some, such knowledge may impact negatively on their identity. Instead of taking preventative measures, a person might become more depressed and develop an identity around the illness. Others may feel ashamed about their proclivity for developing such illnesses and be concerned about keeping the information private because of societal stigma.

Research shows that genetic explanations have different effects on social and self-stigma depending on whether someone is already affected by the mental illness, or if there’s a family history.

The second ethical challenge stemming from explaining an illness as solely caused by genetic factors concerns the notion of informed autonomous choice.

Many complex ethical issues are treated according to a principle-based approach that emphasises informed autonomous choice as the guiding tenet.

My friend considered having a genetic test without adequate information about the inherent risks of new information and little understanding of the science behind the probabilities given by genetic tests. She certainly didn’t consider that such a test might also tell her about the health risks of other people in her family.

Knowing these likely consequences might change people’s decision to undertake a test, and that leads us to the final ethical problem posed by genetic tests being considered in this article – the familial burden that the new information may create.

Not only can some predictive tests provide more information about individuals, in the case of hereditary conditions, they may reveal more than people want to know about their family members.

People may not even want to tell their partners about what they find because of a desire to not burden them with the information. A predictive test may reveal information about other family members or cause concern that our children might develop the same condition in the future.

These are only a few of the emerging pitfalls that accompany the issue of geneticising depression. In the longer term, relying on genetic explanations of depression may in fact cause more unintended harm and increase self-stigmatising attitudes. And this may compound other types of concerns individuals have around insurance discrimination, privacy of genomic information and employment discrimination.

If you think you may be experiencing depression or another mental health problem, please contact your general practitioner or in Australia, contact Lifeline 13 11 14 for support, beyondblue 1300 22 4636 or SANE Australia for information.

This is the fifth article in our short series on depression. Click on the links below to read the other articles:

Part one – Explainer: what is depression?

Part two – Treating depression ethically requires more than drugs

Part three – Predicting the risk of depressive disorder – promises and pitfalls

Part four - The science of interpreting common symbols in dreams

Part six – Are antidepressants over-prescribed in Australia?