Describe the sex-linked recessive gene disorder of color blindness through pedigree analysis.

(N/A) Color blindness is a sex-linked recessive disorder caused by a mutation in certain genes present on the $X$ chromosome.
This defect results in the failure to discriminate between red and green colors due to the defect in either red or green cone cells of the eye.
It occurs in about $8\%$ of males and only about $0.4\%$ of females because the genes for red-green color blindness are located on the $X$ chromosome.
Males have only one $X$ chromosome and a $Y$ chromosome,whereas females have two $X$ chromosomes.
The son of a woman who carries the gene has a $50\%$ chance of being color blind.
The mother is not herself color blind because the gene is recessive and its effect is suppressed by her other normal dominant gene.
$A$ daughter will be color blind only when her mother is a carrier and her father is color blind.