Deuteranopes are missing which photopigment?

Deuteranopes are individuals who have a type of color vision deficiency characterized by the absence of the photopigment associated with the medium wavelengths of light, which is known as chlorolabe. Chlorolabe is responsible for the perception of green colors, and without it, deuteranopes cannot properly detect and differentiate between green and certain shades of red. This condition is a result of a specific genetic abnormality affecting the cones in the retina, particularly the M-cones (medium-wavelength sensitive cones). The absence of chlorolabe results in difficulties distinguishing colors that contain significant amounts of green, which is a key feature of deuteranopia.

The other photopigments listed serve different roles in color perception. Erythrolabe, for instance, is related to red perception, while cyanolabe corresponds to blue light detection. Retinol is part of the visual cycle but is not a photopigment itself; it is involved in the regeneration of photopigments in the photoreceptor cells.