Final answer:
The genotype that confers protection against malaria includes the heterozygous (AS) sickle-cell trait and certain mutations in the glucose 6-phosphate dehydrogenase (G6PD) gene. These genetic variations are advantageous in regions where malaria, caused by Plasmodium falciparum, is prevalent.
Step-by-step explanation:
The genotype that provides protection against the effects of malaria is characterized by the presence of the heterozygous (AS) condition for the sickle-cell trait. Individuals who are heterozygotes for the sickle-cell allele possess one normal hemoglobin gene (A) and one mutated hemoglobin gene (S). This combination results in some red blood cells adopting a sickle shape under certain conditions. However, it also confers a resistance to malaria, particularly against the parasite Plasmodium falciparum, which is responsible for the most severe form of the disease.
Another form of genetic protection against malaria involves mutations in the glucose 6-phosphate dehydrogenase (G6PD) gene. Homozygotes for certain G6PD mutations are less prone to malaria infection. These genetic adaptations are observed in regions where malaria is endemic, such as parts of Africa, Southeast Asia, and South America.
It's important to note that while the presence of one sickle-cell gene (sickle-cell trait) offers resistance to malaria, having two copies (sickle-cell disease) does not provide this benefit, and individuals with sickle-cell disease do not have immunity to malaria.