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CBSE Class 12-science Answered

it is said
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Asked by harshgrewal067 | 22 Apr, 2022, 12:24: PM
answered-by-expert Expert Answer
Below is the answer, if your questions states - 
It is said that the harmful alleles get eliminated from population over a period of time, yet sickle-cell anaemia is persisting in human population. Why?  
 
Solution:
Sickle-cell anaemia is an autosomal recessive disorder caused by haemoglobin defect in the blood cells. Despite the disease's lethal symptoms, it protects the carrier from malaria. Its allele are most common in the people of African descent and some other areas where malaria is prevalent. It provides vital protection from malaria. Individuals with HbAS heterozygotes tend to survive better than individuals with HbSS (homozygotes) as they are not exposed to the same severity of risk. That is why although harmful alleles get eliminated from population over a period of time, yet sickle-cell anaemia is persisting in human population.
 
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Answered by Sheetal Kolte | 22 Apr, 2022, 06:06: PM

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