Question

Even though red-green color blindness is a recessive trait, can a female have red-green color blindness? Explain your answer, including the genotype of a female with red-green color blindness.

Answer 1

f a woman has only one colour blind ‘gene’ she is known as a ‘carrier’ but she won’t be colour blind. When she has a child she will give one of her X chromosomes to the child. If she gives the X chromosome with the faulty ‘gene’ to her son he will be colour blind, but if he receives the ‘good’ chromosome he won’t be colour blind.

Answer 2

A woman may have green-red color blindness when she has two recessive alleles (xx).

Step-by-step explanation:

Green-red color blindness is caused by the absence of sensory cells in the retina (responsible for the sense of sight), or by anomalies that are considered to be of genetic origin. Color blindness affects more men than women, because the color blindness gene is linked to the X chromosome, and men have only one X (XY), while women are XX.

Because they have two X chromosomes, the probability of women being colorblind is minimal, but it is possible if the chromosomes are recessive (xx).