Cone Cells in the Retina (IMAGE) Children's Hospital Los Angeles Caption Cone precursor cells, the photoreceptor cells of the retina that detect color, are in green. The red identifies the protein product of the RB gene, which is needed to suppress development of retinoblastoma. Credit Children's Hospital Los Angeles Usage Restrictions Image may be used in context with reporting this story License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.