Abstract
The olfactory receptor (OR) genes belong the largest gene family discovered in mammals, 1000 genes in mice and 350 genes of humans. These proteins are G-protein-coupled receptors (GPCRs) and their signal transduction pathway is well known, it is similar to that found in other neurotransmitters cells. The expression of the OR gene shows some singularities. Each olfactory sensory neuron (OS…