BIOL 372 Lecture 5: bio 372- lecture 5 notes
Document Summary
Genetic diseases (corrections in green font; deletions in red strikeout) Goal of lecture: to summarize currently known spectrum of genetic diseases, understand how they can be maintained in populations, and discuss the feasibility of genetic causation for diseases of unknown cause. -characterized by sickle shaped red blood cells, which aggregate and disintegrate, and consequent anemia (low red blood cell density) -caused by a mutation in the beta chain of the hemoglobin molecule. -geographic distribution of sickle cell anemia conforms to the historic distribution of plasmodium falciparum. --sickle-cell anemia is moderately common in the mediterranean, india and the persian gulf. -heterozygotes have mortality from falciparum malaria reduced by about 95% -the mechanism by which heterozygotes are protected against malaria is unclear but at least some evidence supports several different mechanisms: --shortened life of red blood cell probably inhibits the ability of plasmodium falciparum to reproduce before the blood cell dies.
