Color Blindness Types

Color blindness affects up to 10% of males in some communities, and on average 7% of males worldwide. Women can have color blindness, but most types of color blindness are sex linked and the dual X chromosomes that females have protect them from it most of the time. To understand the science behind color blindness, visit my how color blindness works (science) page.

The variations of color blindness can be categorised by the effect they have on our ability to see color, as follows:

Red Green Color Blindness

  • Protanomaly is caused by defective L-cones, lowering sensitivity to red hues.
  • Protanopia is caused by absent L-Cones, removing the ability to see reds – a severe form of color blindness.
  • Deuteranomaly is  caused by defective M-cones, weakening the ability to differentiate red and green hues in as much as 5% of all males.
  • Deuteranopia is caused by absent M-cones, giving a moderate inability to discriminate red – green hues.
No color blindness, Red Green color blindness, Blue yellow color blindness, total color blindness
No color blindness, red green color blindness, blue yellow color blindness, total color blindness

Blue Yellow Color Blindness

  • Tritanomaly is caused by weakened S-cones, reducing the ability to distinguish some blue and yellow hues.
  • Tritanopia is extremely rare, resulting from a total absence of S-cones. Removing the ability to distinguish some blues with green, and some yellows with violet.

Total Color Blindness

  • Rod monochromacy is a rare, non progressive inability to distinguish any color, resulting from non functioning or absent retinal cones. Rod monochromacy is typically associated with sensitivity to light (Photophobia) and poor vision.
  • Cone monochromacy is also a rare, total color blindness, however is accompanied by relatively normal vision.

For more information on each of these three forms of color blindness, you can visit their individual pages: red green color blindness, blue yellow color blindness, and total color blindness. For other information, follow the other self-explanatory links on the menu to the left!