You may not believe it, but the percentage of people who need treatment for color blindness is quite large. Approximately 5 - 8% of the all the males and 0.4% of females are affected by this ailment. Almost 10 million, a number which represents 7 percent of the total number of American males are affected by this eye problem. 99 % of the color blind people cannot distinguish between red and green colors. It is found that 9% - 11% of the people of European origin fall prey to this genetic disorder in humans.
An English scientist John Dalton, who was himself affected by color blindness, presented a paper on it in 1798. In his honor, deuternopia, a type of color blindness is referred to as daltonism. In most of the cases, the problem is hereditary. An offspring inherits this disorder from his/her mother. A large proportion of the genes responsible for this are located on the X-chromosomes. A genetic disorder may affect the 3 types of the cone cells that actively detects different colors in the visible light and imparts the color vision to a person.
In females, the sex chromosomes are XX and the males have XY pair. This is why it affects males more than it does to the females. The cone cells are found in the retina of eyes. One type of the cone cells get sensitized when light of a short wavelength falls on them, the second type gets excited when they register light of a medium wavelength and the third type of cone cells can register light of long wavelengths. This capability of the cone cells enables us to see red, green, and blue colors and their hues. If a person is lacking in one or all of these cone cells, it makes him see less or no color.
The severity depends on the percentage of cone cells that are absent in the retina of the eye. In some cases, it is so mild that the affected person may not even know about it. However, a person seriously affected by this difficulty may experience following symptoms:
- He/she may experience trouble seeing colors. He may also fail to register their brightness.
- Differentiating between the different hues of the same or similar color is not possible for the affected person.
- The person may exhibit rapid, side-to-side movements of the eyes in a severe form of this disorder.
The color blind person cannot distinguish between the colors of the traffic lights. If you are one of these unlucky people, you must be curious to know about the causes, which are as follows:
- Color blindness is a genetic disorder.
- It can also occur due to problems or damage to the eyes, nerves, or brain.
- Cataract can also cause this condition in a person.
- Exposure to hazardous chemicals can also be a cause.
- Damage to brain or retina due to shaken baby syndrome.
- Swelling of the brain in the occipital lobe caused by trauma or accidental injury.
- Retinal damage due to exposure to ultraviolet light.
At present there is no cure for color blindness. However, there are some solutions which can be useful in dealing with the problems associated with this disorder. The cataracts that are causing the problem can be removed, which could restore the vision. Color-tinted eye-wear or spectacles can help the person in differentiating the color shades. Special types of contact lenses are also prescribed by doctors to treat it. Laser eye surgery may be helpful in the cases of color blindness that occur after birth.
The latest research in the field of gene therapy shows some sign of finding the cure for color blindness. The scientists successfully developed a gene transfer technique to deliver the corrective genes by using harmless bacteria as the carriers. The primates which were used in the research regained color vision to some extent. It is too early to use this technique reliably in humans, however it is major step in finding the right treatment.
Disclaimer: This article is for informative purposes only, and should not be used as a replacement for expert medical advice.