Color blindness occurs when one or more types of cone cells in the retina are either missing or don’t function properly. The most common form is red-green colorblindness, affecting about 8% of males and 0.5% of females:
- Deuteranomaly: reduced sensitivity to green light
- Protanomaly: reduced sensitivity to red light
- Complete color blindness (achromatopsia): seeing only in grayscale
When cone cells are missing or defective, the brain receives incomplete color information, making it difficult to distinguish between certain colors. This is typically genetic and inherited on the X chromosome, explaining why it’s more common in males who have only one X chromosome.