What percentage of African Americans have sickle-cell trait?

• A. 2-5%
• B. 6-7%
• C. 8-10%
• D. 11-15%

Answer: (C)

The correct answer is that approximately 8-10% of African Americans carry the sickle-cell trait. This trait is a genetic condition caused by the presence of an abnormal hemoglobin gene, which can lead to sickle-cell disease if inherited from both parents. The prevalence of sickle-cell trait in African Americans is significant due to the historical presence of malaria in West Africa; the sickle-cell trait provides some protective advantage against malaria, leading to higher carrier rates in populations from regions where malaria was prevalent. Therefore, the figure of 8-10% reflects the considerable impact of this trait within the African American community, highlighting the importance of genetic screening and awareness for health management.