A person with a defect in color vision (color blindness) can be classified based on the defect in color vision and other features.
Parameters:
(1) color(s) affected
(2) inheritance pattern
(3) number of primary colors seen ( 2 or dichromatic, 3 or trichromatic)
(4) severity of defect
Suffix term for number of colors seen:
(1) anomaly (indicated as " ' "): 3 of 3 colors seen (defective but present to some extent)
(2) anopia (indicated as " - "): 2 of 3 colors seen (associated with absent receptors)
Prefix Term |
Color Affected |
prot |
red |
deuter |
green |
trit |
blue-yellow |
Color Affected |
Inheritance |
Number of Colors Seen |
Severity |
Term |
red-green confusion |
X-linked recessive |
3 |
mild |
protanomaly |
red-green confusion |
X-linked recessive |
2 |
severe |
protanopia |
red-green confusion |
X-linked recessive |
3 |
mild |
deuteranomaly |
red-green confusion |
X-linked recessive |
2 |
moderate to severe |
deuteranopia |
blue-yellow confusion |
autosomal dominant |
3 |
mild |
tritanomaly |
blue-yellow confusion |
autosomal dominant |
2 |
moderate to severe |
tritanopia |
where:
• X-linked recessive inheritance usually affects males with unaffected parents. Daughters may be affected if father affected, but sons of an affected father would not be unless mother is a carrier.
• Autosomal dominant should affect at least one parent and half of the children.
Specialty: Ophthalmology