Question

colorblindness is also a sex - linked trait. in order for a woman to be colorblind, she must inherit the colorblindness gene on both of her x chromosomes. for males, they only need to inherit one copy in order to exhibit the trait. look at the genotype key below and do the punnett squares.
female with normal color vision (homozygous dominant) ( x^{c}x^{c} )
female with normal color vision (heterozygous) ( x^{c}x^{c} )
female with colorblindness (homozygous recessive) ( x^{c}x^{c} )
male with color vision ( x^{c}y )
male with colorblindness ( x^{c}y )
#5. cross a female who is colorblind with a male with normal color vision. what are the genotypes and phenotypes of their children?

Explanation:

Step1: Determine the parents' genotypes

The female is colorblind, so her genotype is \(X^{c}X^{c}\). The male has normal color vision, so his genotype is \(X^{C}Y\).

Step2: Set up the Punnett square

	\(X^{C}\)	\(Y\)
\(X^{c}\)	\(X^{C}X^{c}\)	\(X^{c}Y\)

Step3: Analyze genotypes and phenotypes

• Genotypes: \(X^{C}X^{c}\) (female), \(X^{c}Y\) (male)
• Phenotypes:
• Females (\(X^{C}X^{c}\)): Normal color - vision (carriers)
• Males (\(X^{c}Y\)): Colorblind

Answer:

• Genotypes: Females - \(X^{C}X^{c}\), Males - \(X^{c}Y\)
• Phenotypes: Females - Normal color - vision (carriers), Males - Colorblind