A property professional with nearly 20 years experience of estate agency in Suffolk and North Essex. During that time I have carried out market appraisals on over 5000 residential properties and have helped over 1500 people successfully sell their home.
Therefore, a son from a color-blind mother (who receives the trait from his mother on the X-chromosome) will always be color-blind, regardless of the state of the father (who can only give his son a Y-chromosome).
For example, 0.5% (0.005) of the population are colorblind females X X (0.05 x 0.10 = 0.005). Five percent (0.05) of the population are color-blind males X Y (0.5 x 0.1 = 0.05). This is roughly equivalent to the percentages of color-blind females and males in the U.S. population. Y. In the above cross, four different possible offspring are produced: X Y: Color-blind Boy (1/4 or 25%) X+Y Normal Vision Boy (1/4 or 25%) X X Color-blind Girl (1/4 or 25%) X+X Heterozygous Normal Vision Girl (1/4 or 25%) Note: The heterozygous normal vision girl carries the recessive gene for color blindness.