Americans and Native Americans. African-Americans have the lowest rate of color vision dysfunction. Most people in these groups function to their satisfaction, despite this condition. Color vision deficiencies are usually caused by deficits in one or both classes of cone cell in the retina.
Color deficiencies can also result from optic nerve and retinal diseases, breakdown, or injury.
To date, there are no successful medical treatments for inherited color vision deficiency. People with color vision impairments often become aware of their condition when job duties call for color identification and differentiation. This does not mean that, upon this discovery, their positions are terminated. However, these and other jobs can be made easier with adaptive aids like magnification devices and high-intensity lighting and florescent lighting with blue or red shades which can enhance color recognition. Cutting down on glare and varying the distance from which you view something may also make color identification less anxiety-ridden.