Sickle-cell disease is caused by a single mutation in the dna of a particular gene. a person with this disease has red blood cells that lose their original donut shape and form a sickle shape. people with this disorder suffer from low energy levels, blood clots, and strokes. this is an example of

Pleiotropy

Explanation:

The single gene responsible for expressing many characters/traits is called pleiotropy. The sickle cell anemia disease is pleiotropic that is caused by HBB gene mutation. The mutation results in multiple traits (consequences) due to single gene mutation.

The RBCs shape changed to sickle shape this results in low energy levels, blood clots, and strokes. The mutation forms HbS (hemoglobin S) from hemoglobin beta globin subunits. Thus, this is an example of  Pleiotropy.

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