3. 22q11.2 deletion syndrome, also called DiGeorge syndrome, causes atypical parathyroid glands, a heart defect, and an underdeveloped thymus gland. About 85% of patients have a microdeletion of part of chromosome 22. A girl, her mother, and a maternal aunt have very mild DiGeorge syndrome. They all have a reciprocal translocation of chromosomes 22 and 2.

a. How can a microdeletion and a translocation cause the same symptoms?

b. Why were the people with the translocation less severely affected than the people with microdeletion?

c. What other problems might arise in the family with the translocation?