What is the type of genetic inheritance of daltonism? Is daltonism more frequent in men or in women? What is the physiological explanation for the daltonism?
Daltonism is a recessive X-linked inheritance (gene situated in the nonhomologous portion of the X chromosome). Daltonism is more frequent in men since in them only the single X chromosome needs to be affected for the disease to manifest. In women it is necessary for both X chromosomes to be affected for the disease to come out. The disease appears due to a defect in the gene that codifies a retinal pigment sensitive to red.