PÄR SEGERDAHL Associate Professor of Philosophy and editor of The Ethics BlogInforming individuals about their genetic risks of disease can be viewed as empowering them to make autonomous decisions about their future health.

But we respond to risk information not only as rational decision makers, but also with our bodies, feelings and attitudes.

An American study investigated elderly people whose genetic test results showed a predisposition for Alzheimer’s disease. One group was informed about the risk; the other group was not.

In subsequent memory tests, those who were informed about the risk performed markedly worse than those who weren’t informed.

Knowing the genetic risk thus increased the risk of a false positive diagnosis of dementia. The informed participants performed as if they already were on the verge of developing Alzheimer’s.

The risk with knowing the risk is thus a further complication to take into consideration when discussing biobank researchers’ obligation to return incidental genetic findings to individual participants.

Returning information about genetic risks cannot be viewed only as empowering participants, or as giving them valuable information in exchange for contributing to research.

It can also make people worse, it can distort research results, and it can lead to false diagnoses in clinical care.

Pär Segerdahl

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