Question

Julia had a sibling who died because of a genetic disease as an infant. Before having children, she and her husband Tobias get genetic testing and counseling. They are unlucky.
For the GAA gene, Julia has one normal allele and one totally non-functional allele. Tobias has one normal allele and one totally non-functional allele.

If any of their offspring test positive for Pompe disease, when are symptoms likely to develop (remember, both parents have one non-functioning allele, 0%GAA)?

1.) Before the age of nine months

2.) Anytime during adolescence up through middle adulthood.

Answer 1

The right answer is A.

It turns out that this family possesses in their gene the infantile form of Pompe disease, so the disease will appear early in the offspring.

Pompe disease is caused by a deficiency of lysosomal acid α-glucosidase resulting from mutations in the GAA gene. The clinical spectrum ranges from a rapidly fatal multisystem disorder (classical, beginning before 1 year) to less severe myopathy in adults.

Answer 2

I'm thinking that it is 2