Biology 3592A Study Guide - Mendelian Inheritance, Chromosome, Pairwise Comparison
Document Summary
Most variation found in all human populations at similar frequencies. Other alleles, while present in all groups may display dramatic differences in frequency among population groups. Still other alleles are restricted to certain populations (although not present in all individuals in that population) A new mutation arises in a small population. One copy among all others in population. Random chance in a small population can lead to significant changes in allele frequencies. Changes will smooth out as population increases. When a small subpopulation breaks off from a larger population. Allele frequencies of the subpopulation may not represent frequencies in the large population as a whole. One of the founders of the new group may carry a rare allele. That allele will now have a higher frequency in the new population. Certain mutant alleles may be deleterious in homozygotes but confer an advantage to heterozygotes. Leads to an increase in frequency of the mutant allele.
