Most West Africans and people with origins in that region carry the Duffy-negative FyFy phenotype and are therefore resistant to______ malaria
**Core Concept**
The question revolves around the concept of **malaria resistance** associated with the Duffy-negative FyFy phenotype, commonly found in West Africans. This resistance is linked to the **Duffy blood group antigen**, which serves as the receptor for a specific type of malaria parasite.
**Why the Correct Answer is Right**
The correct answer is related to the fact that the Duffy-negative FyFy phenotype confers resistance to **Plasmodium vivax** malaria. This is because **P. vivax** relies on the Duffy blood group antigen to enter red blood cells. Individuals lacking this antigen, such as those with the Duffy-negative FyFy phenotype, are resistant to **P. vivax** infection.
**Why Each Wrong Option is Incorrect**
**Option A:** Incorrect because it does not specify the correct type of malaria.
**Option B:** Incorrect as it is not related to the Duffy-negative phenotype.
**Option C:** Incorrect because it refers to a different aspect of malaria.
**Option D:** Incorrect as it is not the type of malaria resisted by the Duffy-negative phenotype.
**Clinical Pearl / High-Yield Fact**
A key point to remember is that the Duffy-negative FyFy phenotype is particularly prevalent in West African populations, providing them with a degree of protection against **P. vivax** malaria. This highlights the importance of genetic adaptations in response to environmental pressures, such as malaria.
**Correct Answer:** D. Plasmodium vivax malaria