By Akash Velu Velu, Akash 12/10/11 P2B Abrams

 Color Blindness  Color Deficiency  These are the only two names for color blindness. However, there are many types of color blindness. Here are four:  Protanomaly  Deuteranomaly  Protanopia  Daltonism

What Happens in Color Blindness? Color Blindness is a genetic disorder when a person cannot tell some colors apart. For example, people with color blindness may think that red is green. Color blindness is often mistaken as people seeing in black and white. However, this is not the case. Color blindness is caused because the person with color blindness is lacking a type of cone in their eye that helps see red, green, or blue light. People who have color blindness will also have trouble seeing brightness of colors. In a few cases, color blindness can be caused by a drug called hydroxychloroquine which helps treat arthritis. However, it is mainly a genetic disorder.

How is Color Blindness Inherited? Color blindness is inherited from a gene on the X chromosome. Men have only one X chromosome. On the other hand, women have two. This means that in order for a man to have color blindness, men only need one gene for color blindness(from one parent.) However, women, to be color blind, need a gene from both their parents. If a woman only has one, the normal gene on her second X chromosome will dominate over the color blindness gene. In other words, the gene for color blindness is recessive.

Frequency of Color Blindness Color Blindness is more common in men than in women. This is explained in slide four(the previous slide. ) Since men have only one X chromosome, even if they only get one color blindness gene, that person will be color blind. However, in order for a woman to be color blind, they need two genes for color blindness because women have two X chromosomes, and the normal chromosome is dominant, but the color blind chromosme is recessive. About 1 in every ten men have some type of color blindness. Also, only about 0.5 % of the women born are color blind.

 Color blindness is when a person can’t tell two similar colors apart. As shown in the picture, the signal has the colors red, yellow, and green. However, from a color blind person’s eyes, all the colors look like a type of yellow. There are many types of color blindness. In one type, the affected person may not be able to tell red apart from yellow. For example, in protanomaly, a type of color blindness, the affected person sees the colors red, orange, and yellow as green.

young  Color blindness is usually discovered at a young age as children are learning colors. However, in a few cases, color blindness can be confirmed with a chart that looks the picture on the right. There is no treatment for color blindness. However, there are special lenses and glasses that help people tell colors apart. Color blindness is tested usually at eye doctor offices. On the picture on the right, color blind people should not see the boat.

 It is commonly mistaken that dogs are color blind. However, they are not.  Color blindness is a recessive trait.  People with color blindness get rejected from jobs often.  The name Daltonism is named after a scientist named John Dalton.  Color blind people have the most trouble with matching clothes and getting ripe bananas.  John Dalton was a color blind person.

 Interactive Explorer. Bodyworks San Diego, CA. Quarto Children’s Books, 2010  Daniel Fluck. “50 Facts About Color Blindness”. Colblindor.com Colblindor. blindness / blindness /  Dr. Rabin. “What is Colorblindness and the Different Types?” Testing Color Vision.com. ColorVisionTesting.  science.jrank. “Color Blindness-Inherited or Acquired Defect” science.jrank.org Net Industries and its licensors. acquired-defect.html acquired-defect.html  MedicinePlus. “Color Blindness”. MedicinePlus US Department of Health and Human Services.