Question 1
Selection has obviously affected the frequency of alleles for sickle cell hemoglobin and perhaps the frequencies for cystic fibrosis. What factors might be responsible for inter-population differences in other alleles such as the ABO system?
Question 2
To trace the migration of human populations across the globe, geneticists and anthropologists often make use of genetic markers. What criteria should be used in selecting such markers? What are some of the problems that might be encountered in such genetic studies?