Pheromone phenotypes

The V1r genes encode a large superfamily of receptors that are expressed in the sensory neurons of the vomeronasal organ (VNO) and are thought to be important in pheromone detection and responses. In the 5 September Nature, Karina Del Punta and colleagues describe the phenotypes of mice lacking a large genomic region that contains V1r genes (Nature 2002, 419:70-74).

Del Punta et al. used the Cre-loxP system to engineer a 600 kb deletion in the mouse genome, removing a cluster of 16 genes (12% of the functional V1r repertoire). The mutant mice displayed defects in a subset of VNO-dependent behaviors, including reduced maternal aggression towards intruders and dysfunctions in male sexual behavior. The deletion also abolished the electrophysiological response of the VNO to a subset of V1r ligands (the authors use the term "specific avnosmia").