Network of genes involved in olfactory perception with hub genes distributed in three clusters.

The network shows 135 genes (blue nodes), their co-expression (grey lines) and shared protein domains (green lines) that were identified in our study. About 50 genes are co-expressed at the transcript level; however they are inhibited by negative feedback supporting the one neuron–one receptor hypothesis. All OR genes show shared protein domains. The network generated has a clustering coefficient of 0.9, network density is 0.431 and network heterogeneity is 0.266. Each gene has an average of 57.8 neighbors.