'Doublesex' Gene Key to Determining Fruit Fly Gender

The brains of males and females, and how they use them, may be far more different then previously thought, at least in the fruit fly Drosophila melanogaster, according to research funded by the Wellcome Trust.

In a paper published in the journal Nature Neuroscience, researchers from the University of Glasgow and the University of Oxford, have shown that the gene known as 'doublesex' (dsx), which determines the shape and structure of the male and female body in the fruit fly, also sculpts the architecture of their brain and nervous system, resulting in sex-specific behaviours.

The courtship behaviour of the fruit fly has long been used to study the relationship between genes and behaviour: it is innate, manifesting in a series of stereotypical behaviours largely performed by the male. The male chases an initially unreceptive female, and 'woos' her through tapping and licking and using wing vibration to generate a 'courtship' song. If successful, the female will slow and present a receptive posture, which allows copulation to occur.

For some time now, the gene 'fruitless' (fru), which is specific to the adult male fruit fly, was thought to be the key to male behaviour and the development of male specific neural circuitry of flies.