What Type of Inheritance Is This and Why?

Question

A man with normal vision marries a red-green color blind woman. They have eight children in total (five boys and three girls). All of their sons are born with red-green color blindness, while NONE of their daughters have it.

Answer 1

The type of inheritance experienced here would be sex-linked. This is because color blindness is an X-linked trait. The probability of color-blindness affecting women is less likely due to the presence of two X chromosomes. However, when a female is colorblind X_cX_c both chromosomes must be affected in order to be colorblind. However, in males there is one X and one Y chromosome, when the X is affected by colorblindness X_cY, it is guaranteed that the males will have it. When conducting a punnet square we see that all females will be carriers X_cX and all males will be affected X_cY.