Color blindness is more prevalent in males than in females: about 7% of men are color blind compared to about 0.4% of women. That means for every color blind woman there are about 17 color blind men. This is likely due to the fact that color blindness is part of a defective X-chromosome. Men have only one X-chromosome, where women have two — one good one may make up for one bad one, yielding to fewer color blind women.
More facts:
- The most common form of color blindness is red-green blindness.
- There are various levels of color blindness, which may be more aptly described as color deficiency.
- Though color blindness usually is inherited genetically, it can also be caused by brain damage (e.g., from shaken baby syndrome or traumatic accidents) or damage caused to the retina by ultraviolet light.
- John Dalton, an English chemist who was color blind, was the first to scientifically document color blindness in the late 1700s. The condition is sometimes called Daltonism after him.
- Famous color blind people in the United States include Mr. Rogers, Matt Lauer, Jack Nicklaus and Paul Newman.