Color Blindness

Defect In The Iris

What Is It?

Color blindness, or color vision deficiency, is a reduced ability to distinguish between colors. There is no cure to this disease, but it is certainly treatable. For most affected, it has been inherited from their mother. This can be very difficult to detect. Obviously, colors are impossible to describe, but everybody knows what red is. If you need glasses, there are tests that they can perform. One of these tests can be seen at the right.


In 1794, John Dalton described his own color blindness. Both him and his brother confused scarlet with green and pink with blue. Dalton proposed that his vision was tinted blue. He went in for an exam, but the exam said that he was fine. DNA extracted from his own eye said that he deuteranope, contradicting Thomas Young's belief that Dalton was a protanope.
Image of Professor John Dalton


Frequently Asked Questions

How common is the disorder? It occurs in about one of every twelve men. How can it be inherited? It can be inherited from the mother or the father. But, chemical and physical damage can also cause it. What can I do to stop it? Nothing. If you're color blind, you are color blind for a lifetime.
Normal eye vs. the eye of someone suffering from color vision deficiency
What It's Like To Be Color Blind