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 will have the translocation, and 1/2 will have 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 will have the father's translocation.

Question

Quizplus · Accepted Answer

In cases of balanced translocations in a parent, during meiosis, the segregation of chromosomes can result in different outcomes. Approximately 1/4 of the gametes will be normal, 1/4 will carry the balanced translocation without any genetic material loss or gain (like the father), and the remaining 1/2 will have duplications or deletions of genetic material due to improper segregation, which can lead to unbalanced chromosomal abnormalities.

A Phenotypically Normal Prospective Couple Seeks Genetic Counseling Because the Man