Fleming – three genes

The genes that I’m interested in are mostly those genes that we have a strong basis for believing should be important given what we know about the role of the brain and the role of neurotransmitters. 

In particular dopamine, serotonin, and oxytocin are the three gene types that we’ve been working with. So we find out whether they’re variations in these genes in mothers, and indeed there are. The serotonin transported gene, there’s a lot of variation, three variants of that. Dopamine receptor genes, there are also a number of variants for those genes, as well as oxytocin, which is a gene for a transmitter that’s actually been implicated in bonding and mothering in many contexts. 

Then we look at those variations, we look at the variations of the mother’s behaviour and we try to relate the two. We find, indeed, that there is not only that there are variants say of the dopamine genes, which seem to relate to the variation sensitivity in mothering. But, in general, it’s never a direct effect, or in general it’s not usually a direct effect, so that we also find that how mothers have been raised, that is their early experience interacts with the kind of genotype that they show. For instance with the dopamine genes, with the serotonin genes and with the oxytocin genes, and what that means is that you can have had a bad experience in early life and only if you carry a particular variant of that gene will that early experience be seen in somewhat sub optimal or difficult mothering behaviour, okay. But if you have the other variant of the gene, even though you’ve had a poor early experience, it somehow protects you so that you show less difficulty in your mothering. So that’s what we mean by an interaction, and I think that tends to be the case for many of these gene effects, is they don’t, they’re not really direct effects, it’s not as though if you’ve got a particular gene this is how you’re going to mother. It really does interact with many factors, early experience being a very important one.