Problem:

Question 1: Why does the increased prevalence of sickle cell disease among African Americans have more to do with the environment than skin color or other phenotypes used to define races.

Question 2: What are examples of balanced polymorphism?

Question 3: Other than Africans, what is another population group with a high prevalence of sickle cell disease?

Question 4: What are six genetic diseases that are more common among Ashkenazi Jews than among others?

Include source of information for best answer.