Color blindness, or color deficiency, occurs when an individual is unable to distinguish between certain colors and belongs to the most widespread genetic disorders. This happens “in an X-linked recessive pattern,” as the genes, and mutations that are responsible for the defect, OPN1LW, OPN1MW, and OPN1SW, reside in the X chromosome (“Color vision deficiency,” 2020, para. 11). Males, who have only one, consequently are more probable to develop the disorder because a single genetic change is sufficient to cause it. Meanwhile, in a female, mutated genes need to be present in both of her X chromosomes to result in a color deficiency.
The above genes encode the so-called opsins, the sensitive-light proteins that form retina cones. Each of them responds to a particular wavelength of light and transmits the appropriate signal to the brain that combines the input into the normal perception of colors (“Color vision deficiency,” 2020). The three genes bear the instructions for synthesizing three opsin pigments, which is an example of gene expression. Meanwhile, a mutation in whichever of them interferes with the process, causing defects in the cones of a certain type or their complete absence, which, in turn, makes adequate color perception impossible. Such an effect exemplifies gene suppression, as it limits expression up to its inactivation. It needs clarifying whether this is hypothetically correctable with medical intervention, in other words, whether an artificial reactivation of expression is possible, and if not, why.
Reference
Color vision deficiency. (2020). Medicine Plus. Web.