Question: how can you study a persons behaviour via someones genes?

Darren Logan answered on 13 Mar 2012:

This is what I do! There are various ways of going about this.

The hard part is finding the behaviour genes in the first place, because as Katherine says, there are lots and lots pf genes, and lots and lots of environmental factors that can influence behaviours. I get around that by looking for genes that are involved in instinct (these are the behaviours that are influenced the least by your environment).

So you can look for genes that are turned on on the parts of the brain that are involved in controlling behaviour. You can also make a guess at what gene is involved, based on what it looks like or its shape, or how similar it is to other genes. Or you can use statistics to look at the genes of lots of people who have an unusual behaviour and ask what gene they all have in common. We have found interesting genes using all these methods.

Once you have your “candidate gene”, you then have to test it to see if it really does control behaviour. We often use mice to study the gene in more detail. We may see if that gene is turned on or off in mice when the behaviour happens. Or we may make a genetically modified mouse that lacks the gene, and then we see how that mice behaves. We have done this in the past and made a mouse that is no longer afraid of cats by changing just one gene.

Finally, we may try to find some people with the same abnormal behaviour, and then see if they also have an broken version of the gene.