An individual who has a genetic deficiency of one or more type of cone cells has blindness.

The condition you are referring to is known as "color blindness" or more specifically, "cone cell dystrophy." In the human retina, there are three types of cone cells, each sensitive to different wavelengths of light (long, medium, and short wavelengths, corresponding to red, green, and blue light, respectively). When an individual has a deficiency or absence of one or more of these cones, they are unable to perceive certain colors accurately.

Color blindness can be genetic, often inherited in an X-linked recessive pattern, meaning it is more common in males than females. The most common forms of color blindness include red-green color blindness (which affects the perception of red and green hues) and blue-yellow color blindness.

This condition can significantly affect daily life and activities, particularly those that rely on color recognition, such as certain professions or tasks involving color discrimination. However, many individuals adapt to their condition, using other visual cues to distinguish between colors and navigate their environments.

While color blindness is typically not accompanied by a loss of visual acuity, it can have a profound impact on perception and quality of life.