[Hereditary color vision deficiency: Physiology, classification, diagnosis and application to aeronautics].

Hereditary color vision deficiency affects 9% of men and 0.5% of women. It is often unrecognized and diagnosed late, which can interfere with the professional careers of these patients. Most color vision deficiencies are related to X chromosome involvement and concern the red-green chromatic axis. They are secondary to dysfunction of an L or M cone (protanomaly or deuteranomaly) or to the absence of an L or M cone (protanopia or deuteranopia). Color vision deficiency screening and assessment can be done by confusion tests or equalization tests, but also by ergonomic tests, professional tests that assess the aptitude for a given profession.