A phenotypically normal prospective couple seeks genetic counseling because the man knows that he has a translocation of a portion of his chromosome 4 that has been exchanged with a portion of his chromosome 12. Although he is normal because his translocation is balanced, he and his wife want to know the probability that his sperm will be abnormal. What is your prognosis regarding his sperm?
A)1/4 will be normal, 1/4 with the translocation, 1/2 with duplications and deletions.
B)All will carry the same translocation as the father.
C)None will carry the translocation since abnormal sperm will die.
D)His sperm will be sterile and the couple might consider adoption.
E)1/2 will be normal and the rest with the father's translocation.

Question

Quizplus · Accepted Answer

In a balanced translocation, the individual is phenotypically normal, but during gamete formation, there is a risk of producing unbalanced gametes. In this case, 1/4 of the sperm will be normal, 1/4 will carry the balanced translocation, and 1/2 will have duplications and deletions due to improper segregation during meiosis.

A Phenotypically Normal Prospective Couple Seeks Genetic Counseling Because the Man