In some regions where malaria is endemic, the frequency of the sickle-cell allele is as high as 15% due to heterozygous advantage for increased resistance to malaria. if modern technology were to completely eradicate malaria but not alleviate sickle-cell disease, what would be expected to happen to the sickle-cell allele frequency in subsequent generations?

There will be an increase in frequency, if there is continuous reproduction within humans with the heterozygous genotype but a decrease if there is a continuous reproduction of heterozygous humans and non-carriers of the allele.

Explanation:

The heterozygous genotype gives an advantage for malaria resistance however, if malaria was completely eradicated and the heterozygous genotypes continue to reproduce within one another, there will be an increased frequency of sickle cell allele. However, if heterozygous alleles were to reproduce with individuals without the allele, there will be a decrease in the frequency of the allele in the human population. If this trend continues, there will be ao less a frequency of the allele that it's presence could be completely lost.