The science behind color blindness

Being color blind most often is caused by a genetic condition that is hereditary. In simpler words, people are usually just born with it. Blue as well as red/green color blindness is generally passed from parents to their children. The specific gene which causes color blindness is carried through the X chromosome and can explain it happens more often to men in comparison to women.
In the United Kingdom, 8% of males, and 4.5% of the total population are color blind. Worldwide, there is approximately 250 million people who are color blind. Most people who possess this deficiency have gotten it from their mother. Usually, the mother that gives her child the color blind is interestingly not color blind herself.  There are even people who get this condition due certain diseases, for example diabetes, certain liver diseases, multiple sclerosis and nearly every single eye disease.


What people who are colorblind experience is not always so severe. It really depends on what the defect is.  If color blindness was inherited then the condition will remain constant throughout the person’s entire life, and will see no improvements, however it will also not worsen.
The eye’s retina has two different types of cells which are light-sensitive. They are known as rods and cones.  Both of these cells are located in the retina, which is the layer at the back of the eye. This is what process images. Rods function in conditions with low light in order to assist with night vision, while cones function for daytime light and are in charge of color discrimination.


Cone cells, specifically however, have three different types.  Every type is different in terms of its light wavelengths sensitivity. One of the kinds sees blue light, while another one sees green, and the last one sees red light.  Light enters the eye when looking at an object and this is what triggers the cone cells. The brain following this takes in the cone cells signals, and you can then see the object’s specific color. The blue, red and green cones come together in order to enable the eye to see the entire ray of colors.  That’s how purple is created, with the red and blue cones coming together in a specific way.
What the physical causes of color blindness are has yet to be discovered, however for now, the most popular thought is that it is due to faulty cones, and in some cases due to an error in the path from the cone to the brain.  Those who have a regular color vision have all of the cone and pathways properly working together. So what differs with color blind people is that at least one of these is faulty.

Shockpedia