In my field of research there is quite a 'famous' example of how a gene may change behaviour. The distribution of vasopressin and oxytocin receptors in the brain can exhibit profound species differences; e.g., the montane and prairie vole have strikingly different patterns in vasopressin V1a receptor expression. It has been shown that vasopressin is important for affiliative behaviour, such that this ‘neuro’hormone increases olfactory investigation and grooming (towards a female) in the highly social, ‘monogamous’ male prairie vole but not in the relatively asocial, ‘promiscous’ male montane vole. If you engineer a mouse (relatively ‘promiscuous’) to express a prairie vole-like V1a receptor distribution in the brain (e..g., by introducing the prairie vole V1a receptor gene into the mouse) then this animal has pro-social response to vasopressin, i.e., behaves more like a ‘monogamous’ animal!
This does not mean that only the V1a receptor is responsible for pro-social behaviour (or for example, that generating a prairie vole-like brain distribution in a mouse has not altered other genes and/or neural wiring) but it does seem to suggest that changes in the (pattern of) expression of a single gene can influence some types of behaviour.
See - http://www.ncbi.nlm.nih.gov/pubmed/10466725
Last edited by Steve Lolait (13th Feb 2016 10:33:43)