Editing Color blindness (section)

====Genetics of red–green color blindness====
{{main|Congenital red–green color blindness#Genetics}}
[[File:Punnett square colour blindness.svg|thumb|alt=A chart showing likelihoods of genetic combinations and outcomes for red–green color blindness|Punnett squares for each combination of parents' color vision status giving probabilities of their offsprings' status; A superscript 'c' denotes a chromosome with an affected gene.]]
By far the most common form of color blindness is [[congenital red–green color blindness]] (Daltonism), which includes protanopia/protanomaly and deuteranopia/deuteranomaly. These conditions are mediated by the [[OPN1LW]] and [[OPN1MW]] genes, respectively, both on the [[X chromosome]]. An 'affected' gene is either missing (as in Protanopia and Deuteranopia - [[Dichromacy]]) or is a [[chimeric gene]] (as in Protanomaly and Deuteranomaly).

Since the [[OPN1LW]] and [[OPN1MW]] genes are on the X&nbsp;chromosome, they are [[Sex linkage|sex-linked]], and therefore affect males and females disproportionately. Because the color blind 'affected' [[alleles]] are recessive, color blindness specifically follows [[X-linked recessive inheritance]]. Males have only one X&nbsp;chromosome (XY), and females have two (XX); Because the male only has one of each gene, if it is affected, the male will be color blind. Because a female has two alleles of each gene (one on each chromosome), if only one gene is affected, the dominant normal alleles will "override" the affected, recessive allele and the female will have normal color vision. However, if the female has two mutated alleles, she will still be color blind. This is why there is a disproportionate prevalence of color blindness, with ~8% of males exhibiting color blindness and ~0.5% of females.