Sickle-cell anemia and malaria - Essay Example

In other words, there are some natural selection traits that favor sickle cell-anemia allele in some individuals. Malaria occurs in the tropical zones and is caused by a protozoa transmitted by the anopheles female mosquito. As such, people from an African descent have the sickle cell anemia allele considering that heterozygotes for the allele are protected from malaria while not showing any significant characteristics of sickle-cell anemia. These people can then live to adult age and transfer these alleles to their offspring, which guarantees the transfer of the allele along the genetic line of individuals, leading to a new gene pool.

Therefore, for some recessive alleles that are destructive to the recessive homozygotes, natural selection is an important process through which the heterozygotes of the recessive alleles have to survive (Sabeti, 2008). For instance, when an individual carrying the sickle cell allele is in an area where malaria is not prevalent, having the sickle cell anemia allele does not guarantee any survival advantage. As such, in countries such as United States, there are much fewer cases of sickle cell alleles compared to tropical regions such as in Africa.

However, the disease is still reported among people of the African descent, though on low frequencies. This is because, the time required for the allele frequency to reduce significantly to negligible amounts has not passed. With the passage of time, the sickle cell anemia may become extinct in these areas. Application of advanced technologies would ensure individuals are in a position to make better and informed decisions on reproduction, which may help in ensuring extinction of a number of genetic diseases from passing through