For the first time, researchers have transformed an antisocial mouse into a more social animal by genetically manipulating the distribution of a specific receptor in the brain.
Neuroscientists at Emory University created a transgenic mouse by inserting a gene from a prairie vole, a rodent species known for its fidelity and sociability. The new mouse showed the brain receptor distribution and even adopted the social behaviors of the gregarious prairie vole. Their work is described in the August 19 issue of the journal Nature.
In trying to uncover the neurochemical mechanisms behind bonding and attachment, Drs. Tom Insel and Larry Young have long studied vasopressin, a naturally occurring peptide hormone produced in the brains of most mammals, including humans. In voles, the scientists previously showed vasopressin to be important in male social and reproductive behaviors, determining the real influence to lay in the distribution of the hormone's receptors, not the amount of the hormone itself. They found receptor distribution to vary greatly between species with marked contrasts between monogamous and polygamous mammals. In the new research they inserted the vasopressin receptor gene from a monogamous vole into a less social, polygamous mouse. This is the first time that a single gene has proven sufficient to change complex social behaviors so dramatically.
"These transgenic mice really surprised us," says Dr. Young, "not only did they show the prairie vole pattern of vasopressin receptors, but these mice responded to vasopressin just like prairie voles." While these transgenic mice were not monogamous, when given vasopressin they showed an increase in social contact with a female, a response that was not seen in normal mice.
Vasopressin has previously been shown to play a role in male social
behaviors such as communication, aggression, sexual behavior, and social memory.
In monogamous species, such as the
Contact: Kate Egan
Emory University Health Sciences Center