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What is an example of mutation?
The disease sickle cell anaemia occurs due to a mutation. This causes the amino acid glutamic acid (which is hydrophilic) in haemoglobin to be replaced by valine (which is hydrophobic).
Why are not Americans affected with sickle cell anaemia?
natural selection and heredity Americans are affected with sickle cell anaemia which mostly affects black people.
Where in the world are the most cases of Malaria and Sickle Cell anaemia?
Malaria is common in topical ad subtropical zones. The malaria has selected the people with sickle cell anaemia. Although person with sickle cell anemia can have malaria, the carrier, or the person with sickle cell trait is resistant to malaria.
Can you explain what evolutionary advantage mean and how it accounts for why sickle cell anaemia is still so widespread in Africa?
evolutionary advantage means that if you have to types of sickle cell anaemia and one is resistant to a drug the the other one is not then the one that is not resistant dies off and the sickle cell anaemia that is resistant becomes dominant and that is why sickle cell anaemia is still so widespread in Africa because the strain that is widespread in Africa is resistant is anti-biotics.
Why is sickle cell prevalent in Africa?
In haemoglobin, there are four polypeptide chains that make it's structure, 2 (A) chains and 2 (B) chains. Sickle-Cell Anemia is caused by a mutation the (B) chain that makes the haemoglobin molecules stick to each other and form fibres inside the red blood cell (RBC). Instead of a circular disc shaped RBC we now have a sickle shaped cell. This means transport of oxygen is very innefficient and the disease can cause death. However, in areas with a high malaria rate, heterozygous sickle-cell anaemics (with some sickle shaped AND normal RBCs) are naturally selected because the protozoan (what causes the disease) is unable to live inside the red blood cell due to the fibres formed from the mutation, the cells are more fragile and they have a shorter life span than normal RBCs. This means that people with heterozygous alleles for sickle-cell anaemia benefit against malaria and will survive to reproduce, which increases the allele frequency of the sickle-cell anaemia allele. Those with homozygous sickle-cell anaemia and those with homozygous normal haemoglobin are selected against as the first usually die of the sickle-cell anaemia, and the latter contract malaria. NB. Mutations are rare occurrences. It is even rarer for a mutation to give selective advantage. This mutation for sickle-cell anaemia did not happen to 'cure' or prevent malaria, it was a random occurrence that coincidentally gave a selective advantage against malaria.
How does sickle cell anaemia cured?
Sorry there is no cure only treatment.
What are the drugs contraindicated in sickle cell anaemia?
Most of them I would imagine.
How many people in the UK have sickle cell anaemia?
15000 people with sickle cell in the UK i think
What is the difference between thalassemia and sickle cell anemia?
Though Thalassemia and Sickle Cell Anemia are seemingly similar to the unknowing, a large difference remains; Thalassemia is characterized by a reduced production from one of the globin chains which make up hemoglobin while in Sickle Cell Anemia, the globin chains themselves are structurally defective.
Do people die from sickle cell anaemia?
20,000 people die with sickle cell each year
Is sickle cell anemia a single gene defect or multiple gene?
Sickle Cell Anaemia is a single gene defect (Hb gene).
Which is a degenerative disease atherosclerosis malaria rickets sickle cell anaemia?
antherosclerosis
