• Question: How large is the role that genetics plays in determining traits more related to personality and habits?

    Asked by to Richard, Reka, Oliver, Judith, James, Gemma, Emma, Ed, Bobby, Anthony on 28 Dec 2018. This question was also asked by .
    • Photo: Ed Morrison

      Ed Morrison answered on 28 Dec 2018:


      This area of science is called “behavioural genetics”. We get answers from studies of twins (identical vs. non-identical) and people who have been adopted away from their parents. If identical twins are more similar then non-identical twins, this tells us that genes are important.

      These studies reveal very consistently that about half the differences between people are due to genes, and half not due to genes. Intuitively we often assume the non-genetic half is how you are raised, but the same behavioural genetic studies show this is probably not the case. How you are raised makes very little difference (often so small it cannot be measured). So this half is things like random events, things happening in the womb, and idiosyncratic interactions throughout life.

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