What is the probability II2 is a carrier of the disease numb

What is the probability II-2 is a carrier of the disease (number between 0 and 1)?

The answer is 0.5

II-1 and II-2 are expecting a child. The sonogram shows they will be having a son. What is the probability he will develop the disease late in life?

The answer is 0.25

II-1 and II-2 have their son. At an early age, it is apparent that he is color-blind. What is the chance he will develop the disease late in life?

Need the answer for this. I can\'t seem to solve it.

disease DEB color blind pedigree color blind and disease A recessive trait for a late-onset neurological disease is located 8 map units from the recessive deutan color blindness trait, on the X chromosome. Below is a pedigree from a family in which both traits are found. The woman\'s husband is color-blind, and she has two sons who show the disease but are not color blind. Her daughter shows neither trait, and is well past the age where the symptoms appear.

Solution

X^c X x X^c X

When II-1 and II - 2 have a son at an early age with color blindness, the probability that he will develop disease late in life is 0.25 The chance of developing disease is therefore, 25% (0.25 x100 = 25%).

male / female	Xc	X
Xc	Xc Xc	Xc X
X	Xc X	X X