The conducted statistical analysis showed that five mRNAs statistically significantly differentiated breast cancer sections regardless of subtype compared to control samples; these were dopamine receptor 2 (<i>DRD2</i>), dopamine receptor 3 (<i>DRD3</i>), dopamine receptor 25 (<i>DRD5</i>), transforming growth factor beta 2 (<i>TGF-β-2</i>), and caveolin 2 (<i>CAV2</i>). This evidence concerns the gene DRD5 and breast cancer.