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3.5.4.1.1. More color blindness problems or daltonism

Sex-linked genetic inheritance problems. Colour blindness or daltonism. (Page 18)

Genetics problem 143

Answer the following questions:

A. A couple, both of whom have normal vision, have a color-blind male child. What is the probability that the couple will have a color-blind daughter? Argue your answer.
B. What is the probability that the couple will have a child with normal vision? Argue your answer.

Genetics problem 144

Genetics problem. Use the appropriate nomenclature: (2 points)

a) Can a child with normal sight have a color-blind father? And a colorblind mother? Reason for all answers based on possible genotypes.
b) Can parents with normal vision have a color blind child? And a colorblind daughter? Reason for all answers based on possible genotypes.

Genetics problem 145

Taking into account that color blindness is caused by a recessive allele linked to sex, solve the following sections. SUGGESTED NOMENCLATURE: Xd, color blindness.

a. List the genotypes of the following two families:

Colorblind woman, whose mother was not colorblind, and whose father was colorblind.

Non-color blind man, whose mother was a carrier of color blindness and whose father was color blind.

b. If the man and the woman in the previous section have offspring, what could their genotypes and phenotypes be?

Genetics problem 146

A woman is heterozygous for a recessive sex-linked gene that causes color blindness. If you have offspring with a non-color blind man,

a) How likely are they to have color-blind sons?

b) What is the probability of having male carrier children?

c) How likely are they to have daughters who are colorblind?

d) How likely are they to have carrier daughters? Justify your answers.