Question

Red green colourblindness is a sex linked trait. Which of the given statements is not correct regarding colourblindness ?

• A. It is more common in males than in females
• B. Homozygous recessive condition is required for the expression of colourblindness in females
• C. Males can be carriers of the trait
• D. Colourblind women always have colourblind father and always produce colourblind son

Answer 1

Answer: (C)

Males can be carriers of the trait

Answer 2

Since colourblindness is a sex-linked recessive trait and males just have one $X$ chromosome, they can never be the carriers. Males will always express the disease/phenotype.