Answer: ½ Colorblindness is an X linked recessive inheritance. Affected father passes on the chromosome to all of his daughters. For a carrier female, with each pregnancy there is a one in two (50%) chance her sons will inherit the disease allele and a one in two (50%) chance her daughters will be carriers. GrandFather: XcY XcY (father) x XcX (mother) Son: XcY or XY Hence: 50% probability or 1/2 Solution Answer: ½ Colorblindness is an X linked recessive inheritance. Affected father passes on the chromosome to all of his daughters. For a carrier female, with each pregnancy there is a one in two (50%) chance her sons will inherit the disease allele and a one in two (50%) chance her daughters will be carriers. GrandFather: XcY XcY (father) x XcX (mother) Son: XcY or XY Hence: 50% probability or 1/2.