Question

High carrier frequency of the mutant G6PD allele is likely due to its protective role against Plasmodium falciparum malaria. What is the reason for the high carrier frequency of the mutant G6PD allele?

1) It provides resistance against Plasmodium falciparum malaria
2) It increases the risk of Plasmodium falciparum malaria
3) It has no effect on Plasmodium falciparum malaria
4) It is unrelated to Plasmodium falciparum malaria

Answer 1

The high carrier frequency of the mutant G6PD allele is due to its resistance against Plasmodium falciparum malaria, which provides a survival advantage in regions where malaria is a significant health concern and leads to a higher prevalence of the trait.

Step-by-step explanation:

The reason for the high carrier frequency of the mutant G6PD allele is that it provides resistance against Plasmodium falciparum malaria. Individuals heterozygous for the G6PD mutation have a reduced risk of severe malaria, which leads to a survival advantage in regions where malaria is endemic. Therefore, this trait tends to be more prevalent in populations from regions such as Southeast Asia, Africa, and South America where malaria is a significant health concern.

In regions where malaria is common, carrying the mutant G6PD allele can confer a selective advantage, increasing an individual's fitness by enabling better resistance to the disease. This is an example of a balanced polymorphism, similar to the way heterozygotes for the sickle-cell allele (AS) are resistant to malaria. This protective effect against malaria helps in maintaining the high frequency of such alleles in the gene pool.

As Plasmodium falciparum evolves resistance to anti-malarial drugs, understanding genetic factors like the G6PD mutation plays a crucial role in controlling and treating malaria. This highlights the need for continuous scientific research to develop new drugs or drug combinations to tackle the evolving challenge presented by malarial parasites.