Presentation is loading. Please wait.

Presentation is loading. Please wait.

Mutations and sickle cell anemia

Similar presentations


Presentation on theme: "Mutations and sickle cell anemia"— Presentation transcript:

1 Mutations and sickle cell anemia

2 As result this change will affect protein function.
A mutation is a change that happens in DNA sequence (A,C,G,T), either due to mistakes when the DNA is copied or as the result of environmental elements for example Smoking, UV light and radiation. Mutations can occur anywhere from a single (base pair) to a large segment of a chromosome that includes multiple genes. As result this change will affect protein function. Mutation can also disturb a normal gene expression and cause disease ( CANCER). Original SEQ. Mutated SEQ.

3 Mutations are divided into two classes:
Heredity mutation:( also known a germ line mutation) inherited from a parent and exist in every cell in the body. Acquired (somatic mutation): happen during person’s life and just found in certain cells. Each cell relies on thousands of proteins to do their jobs in the right places at the right times. Sometimes, gene mutations stop one or more of these proteins from function properly. When a mutation changes a protein that has a critical role in the body, it can disrupt normal development or cause a medical condition. A condition caused by mutations in one or more genes is called a genetic disorder. In some cases gene mutations are so severe, which prevent the fetus from surviving until birth.

4 Change the sentence. The effect depends where the mutation happens
Mutations may be harmful or beneficial or not effected on the organism. The Cat ate the Rat ThC Cat ate the Rat Little effect. But we still have the idea The Hat ate the Rat Change the sentence. The effect depends where the mutation happens

5 Silent mutation. Missense mutation. Nonsense mutation.
Gene mutations have a vary effects on human health based on where mutation occurs as well as gene function, so mutations types are: Silent mutation. Missense mutation. Nonsense mutation. Frameshift mutation

6 Silent mutation: not changing an amino acid, but in some cases can still have a phenotypic effect, e.g., by speeding up or slowing down protein synthesis, or by affecting splicing.

7 Missense mutation: change in one DNA base pair, leads to changing in amino acid, so another protein may be made.

8 Nonsense mutation: change in DNA base pair, so, changed DNA send a signal to deter making a protein, that leads to produce shorter protein (not function at all or function improperly).

9 Frameshift mutation: Addition or loss of DNA bases changes a gene's reading frame. A reading frame composed of groups of 3 bases that each code for one amino acid. Protein is nonfunctional

10 Blood genetics disorders:
Sickle cell anemia Red blood cells carry oxygen to the body and appear like a disc. Hemoglobin gives red cells their color and has two subunits. Hemoglobin molecule (made of alpha and beta globin subunits) picks up oxygen in the lungs and releases it when the red cells reach the tissues, such as the muscles. structure of human haemoglobin. α and β subunits are in red and blue, and the iron-containing heme groups in green.

11 Sickle cell anemia The sickle cell has a single change in the amino acid of hemoglobin. Alpha subunit is normal in people with sickle cell disease. The beta subunit has the amino acid valine (GTG) at position 6 instead of the glutamic acid (GAG) that normally occurs.

12 It is an autosomal recessive disorder If the child receives only one sickle cell anemia allele from parent, he is a sickle cell trait. People with sickle cell trait are fine. Thus, The presence of two mutant genes (SS) (hemoglobin S) is required for sickle cell anemia. Hemoglobin S shortens the life of red blood cells (from ∼120 days to no more than 20 days, normally ∼16 days) and causes the cells to become rigid and crescent shaped rather than round. The stiff, sickle-shaped red blood cells block small blood vessels, leading to reduced blood flow and consequence damage of the tissue and organs.


Download ppt "Mutations and sickle cell anemia"

Similar presentations


Ads by Google