Harvard University researchers studying mice have uncovered a piece of the genetic code necessary for a mother to nurture her young, according to the latest issue of the scientific journal Cell.
Michael Greenberg and his colleagues found that when they bred mice with a defect in a gene known as fosB, the mice did not properly nurture their pups.
This is the latest study to demonstrate a chemical basis for important brain activities.
Researchers know that birth normally sparks a nurturing response in mammals such as mice, dogs and humans.
Contact with a newborn through smell, touch and other senses appears to create a chemical cascade in the body that affects a portion of the brain known as the preoptic area, located in the hypothalamus.
In the female mice with defective fosB gene, their hormones seemed primed and ready to nurture when their pups were born, but contact with the newborn failed to spark the nurturing response.