Normal female, whose father was color blind married a normal man. What are the chances of color blindness in son -
Ans. is 'b' i.e., 50% o Father of the female was color blind; that means she has received mutated X-chromosome from her father and she is carrier for colour blindness. If this female gives bih to a male child there is 50% chance that he will get the disease because the carrier female is carrying one normal X-chromosome and one mutated X-chromosome. Note ? o Here I would like to mention one impoant fact that this question has been asked specifically for the chances of disease in a son. The question can be framed in following different ways. i) How many children will have the disease. ii) What are the chances of son getting the disease. iii) What are the chances of daughter getting the disease. iv) How many son will have the disease. o Thus :? i) 25% of children will have disease. ii) 50% of son (1 out of 2) will have disease. iii) No daughter will have disease. iv) Chances that son will have disease is 50% (1 out of 2 male child can get the disease).
25%
50%
75%
No chance