The virus stains in red the connections leaving the neostriatum wherever it is expressed, but not everywhere as was expected. In the engineered mouse strain the neurons were already fluorescent and the red mixed with the green to form an orangish-yellow hue in the locality of the neostriatum. Within this orangish-yellow zone, are green 'islands' which the virus spared. These are the 'patch' cell groupings. In regular mice, these areas would be a distribution of dark patches.