One in ten is color blind

When light enters through the pupils, it hits the retina at the back of the eye. The retina is filled with light-sensitive sensory cells called rods and cones.

Rods are responsible for registering movement and contrast in our surroundings, while color vision is part of the responsibility of spikes. The cones convert light waves into nerve signals, which are sent through the optic nerve from the retina to the visual cortex at the back of the brain.

We have three different types of faucets, which capture light waves in red, green, and blue, respectively. The stimulus the taps are exposed to determines the colors we see. For example, if red cones are stimulated more than green cones, we see red — and vice versa. Other hues and shades of color appear depending on how intense and combinations the taps of the three species are at the same time. For example, we see yellow when both the red and green cones are intensely stimulated.

Tappers’ different photoreceptors give them their color specialization. Photoreceptors are light-sensitive proteins that capture light at specific wavelengths. When the protein is stimulated by light, a chain of signals is triggered, which are then transmitted to the brain and form a colorful picture of the surroundings.

The genes responsible for the formation of photoreceptors are found on the X chromosome. So it is errors in these genes that cause color blindness. Mutations in genes alter the receptors and impair their ability to – to a greater or lesser extent – register light and transmit it to the brain.

There are different types of color blindness depending on which photoreceptors are not working properly. The most common is green color blindness, deutan, which is caused by cones with green light receptors that are defective.

Red color blindness is called protan and is caused by errors in the receptors that pick up red light. The last and rarest variant is tritan, which affects cones sensitive to blue and interferes with the ability to distinguish between blue and green, as well as between yellow and red.

Scientists will color the world

Although colors are important to our ability to navigate the world around us, most people with color blindness manage to live well without serious problems, despite poor color vision.

However, in some professions, such as pilot and sea captain, sharp vision and flawless color vision are essential, which means that color blind people cannot be employed in those occupations.

But soon there may be help for colorblind people who dream of becoming pilots, or who long to see natural colours. To date, inherited color blindness is considered incurable. But the researchers are now hopeful that it will eventually be possible to correct it.