Although people in the United States know about the sickle-cell allele mainly through the experience of African-Americans, this is by no means an exclusively African phenomenon. The same point mutation has apparently arisen independently two or three times in Africa, at least once in the Middle East, and at least once in Asia. In addition, human migration and intermarriage, along with the wide geographic spread of malaria, have distributed and maintained these alleles in many populations, including (but not limited to) many "European-looking" inhabitants of Greece, Spain, Portugal, and Turkey.
Although people in the United States know about the sickle-cell allele mainly through the experience of African-Americans, this is by no means an exclusively African phenomenon. The same point mutation has apparently arisen independently two or three times in Africa, at least once in the Middle East, and at least once in Asia. In addition, human migration and intermarriage, along with the wide geographic spread of malaria, have distributed and maintained these alleles in many populations, including (but not limited to) many "European-looking" inhabitants of Greece, Spain, Portugal, and Turkey.
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