Here is a pedigree for colorblind (H)
What is fred's genotype?

Answer:
[tex]x^{h} y[/tex]
Explanation:
Fred has inherited the colorblind trait from his mother. We know this because his spot on the pedigree is filled in. Because he is a male his genotype must be some variation of xy and because he is colorblind he must have the recessive "h" on his x chromosome. So his genotype (genetic type) is [tex]x^{h} y[/tex]