Colorblindness is an X chromosome-linked, recessive trait. None of the children of a normal mother (X^CX^C)and a colorblind father (X^cY)could possibly be colorblind.

In familial hypercholesterolemia, homozygous people with the abnormal gene have extremely high cholesterol, while heterozygous people have somewhat high cholesterol. This type of inheritance is called

In sex-linked traits, the cells of all offspring contain two copies of the genes for these traits.