Two colleagues gave blood for an emergency. Ned got infected with HIV because they re-used a needle. His friend Nate was not infected. Which colleague had a virus that originated in sub-Saharan Africa?
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Answer: Ned

Norm and Ian were two brothers. Norm was a totally normal individual, while Ian had Down syndrome. Their parents loved them both equally. Which brother had a nondisjunction of chromosome 21?
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Answer: Ian

Two twin sisters were taken to the doctor's office by their parents. It turned out that Mary had hemophilia while Ann didn't have any blood disease. Which sister was less exposed to the risk of internal bleeding?
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Answer:
Ann