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| Human Genetic Variation and Disease |
Disease has continued to have a strong impact on human mortality and reproduction. One would expect there to be genetic variation for the ability to resist disease. Indeed, there is such variation. Moreover, biologists have been increasingly able to correlate variation at specific genetic loci, and susceptibility to or severity of various diseases. For example, scientists are combining genetic and genealogical data to locate genes that affect disease tendency in Icelanders.
Genetic variation for disease resistance and natural selection associated with disease has shaped the evolution of our species. Below, we discuss the impact of two infectious diseases: malaria and HIV. We conclude with a discussion of the genetics of asthma propensity -- an illustration of the complex interplay of genetics and environmental effects.