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Sickle Cell and Malaria

APBIO-LFXK5V

Sickle cell anemia is caused by the mutation of a single base pair in the gene for hemoglobin. This mutation results in hemoglobin molecules that form long chains in low-oxygen settings and stretch the blood cells into their characteristic sickle shape.

Malarial parasites are less able to enter cells that are affected by the sickle mutation.

How would this affect the likely phenotypic distribution of this allele?

A

The allele would be more common in areas with high malarial activity.

B

The allele would be less common in areas with high malarial activity.

C

The allele would be more common in areas with low malarial activity.

D

The allele distribution would be dependent on random assortment during meiosis and unaffected by environment.