Question 44
Chromosomes, DNA and Sex LinkageThe illustration below represents a cross between a colour-blind male and a normal female. What is the genotypic ratio of carrier females to normal males in the cross?
- A.1 : 1
- B.2 : 3
- C.3 : 4
- D.4 : 1
Show the answer and explanation
Answer: A (1 : 1)
Explanation
The offspring are XcX, XcX, XY and XY: two carrier females and two normal males, a ratio of 2 : 2 = 1 : 1.