Causes of color blindness
The most common form of color blindness is inherited. However color blindness can also be caused by diseases such as macular degeneration, poisoning and side effects of medication. Women are usually the 'carriers' of the defect which is passed on through a defective x chromosome. It is mostly men who inherit color blindness, affecting about 1 in 20 men for every 1 in 200 women.
Color blindness explained
In Color blindness there are a reduced number of cone cells in the retina of the eye. It is the retina that is responsible for color vision.
There are three types of cone cell, red, blue and green cells, that are sensitive to light. The type of color blindness a person experiences depends on the degree of damage and on which groups of cells are affected.
Vision itself is not affected, only the ability to distinguish between certain colors.
Common Forms of Color Blindness
The most common form of color blindness is red/green color blindness. It is passed on through a faulty color vision gene on an X chromosome as a recessive disorder. This type affects about one in 10 men and has two forms. In one form different shades of red appear dull and indistinct and in the other greens, oranges, pale reds and browns all appear as the same hue, distinguished only by their intensity.
Rare Forms of Color Blindness
In one rare form of color blindness, blues and yellows cannot be distinguished. Another rare form of color blindness means that all colors are seen in black and white.
Is there a cure for Color Blindness?
There is no cure for defective color vision that is inherited. Color blindness caused by disease or medication side effects can sometimes be treated.