Would you take gene therapy for monogamy?
Eventually, gene therapy might be perfected as a mechanism of modifying people's courtship and mating behaviors, but "can do" and "should do" questions remain.
Behold, the humble vole. It mostly looks like an extra plump, longer-haired field mouse; but, in its different varieties, it has begun revealing that there might be a genetic basis for different styles of mating and family rearing among mammals.
First, consider the prairie vole, common to North America's grasslands
What makes it unusual among mammals is that it is both sociable and monogamous. Prairie voles groom each other, nest with one another, collaborate to guard their territory and are affectionate and attentive parents who form, for the most part, devoted couples.This behavior is in contrast to its relative, the meadow vole, which "prefers a solitary, promiscuous existence." But the meadow vole can be modified: "it is possible to inject a viral vector for the vasopressin receptor into the brains of the fickle meadow voles and make them better partners and parents."
The differences in behaviors between these two species of vole are due only to a small set of genetic differences:
a hormone called vasopressin and the protein molecule that acts as its receptor. Prairie voles have many vasopressin receptors in the reward centres of their brains. It seems as though these are wired up in a way that causes the animal to take pleasure from monogamy.Vasopressin receptor variations in people have been linked to problems in marriages as well. So now arises a bioethics issue:
Suppose you find yourself dating a high quality person: she or he is intelligent, healthy, physically attractive, and from a very stable family environment. As these things go, you both declare your love to one another, solely and forever, and your intentions to have a family together. One day, the partner of your dreams says s/he has a really serious question to ask you.
S/he reminds you that s/he has worked for some time at a major research center for mammalian genetics, and that there is now no doubt about the tripartite vasopressin to brain function to monogamy behavioral link. In fact, even mammals that do not usually exhibit monogamous or child-labor sharing behaviors can be induced to do so by a simple injection of a viral-implanting vector. Your partner (rightly, it turns out) says that your mutual declarations of eternal love and commitments to family participation could now rely upon more than just the too often unreliable, existential exercise of the will, but upon the assurance of a strong, undeniable natural urge (likeunto the strong, undeniable natural desire for sex or food). It would only be a one-time, simple injection.
"My love," s/he asks, "shouldn't we guarantee our commitment forever?"
 "Monogamouse" The Economist Dec. 30, 2009.