Q. A man’s grandfather has galactosemia, a rare autosomal recessive disease. The man married with a woman whose sister had galactosemia. The woman is now pregnant with their first child.

a. Sketch the pedigree as described.

b. What is the possibility that this child will have galactosemia?

c. If the first child has galactosemia, what is the probability that the second child will have it?