The term daltonism derives from the name of the English John Dalton, chemist and father of the Atomic Theory, who first described the disorder, which he himself suffered.
The scientist, in fact, realized that the grass and blood appeared to him of the same color and thus began to investigate what differences there were between him and other people.
Dalton had an insensitivity to the green color and since the brother also had the same defect, he hypothesized that this anomalous chromatic perception was due to a hereditary disease that brought the vitreous humor to be blue, rather than transparent.
In 1794, Dalton exhibited the first scientific report on color vision entitled " Extraordinary facts relating to the vision of colors ". However, not being able to explain the exact causes of his own color blindness, he gave instructions for his eyeballs to be removed and studied after his death.
Thanks to the important scientific contribution of Dalton, today we know that color blindness (or dyschromatopsia ) is caused by genetic alterations of the cones (photoreceptors of the retina) and, in most cases, manifests itself as a disturbance in the perception of red and of the green.
