Sickle cell anemia is an inherited disease where normal red blood cells sickle in shape.

They sickle because HgbS, (abnormal form of hemoglobin protein), is produced instead of normal HgbA.

The sickle shape of the cell ↓’s the ability of the RBC’s to carry O2 & move through the capillary. They often clump together forming clots.

Normal RBC’s last ~120days.

Sickled RBC’s cells only last about 15 days

↓ blood cells anemia

Signs/Symptoms similar to other types of anemiaHeadacheShortness of breathDizziness Chest pain Pale skinJaundice***FatigueEye Problems

Jaundice is a yellow color in the skin, the mucous membranes, or the eyes. The yellow pigment is from bilirubin, a byproduct of old/destroyed red blood cells.

Hemoglobin, the iron-containing protein in red blood cells that carries O2, is released from the destroyed red blood cells after the iron it contains is removed. The chemical that remains in the blood after the iron is removed becomes bilirubin normally broken ↓ in the liver. (↑ RBC destruction = ↑ bilirubin liver can’t keep up)

As a result of the sickle shape, these cells block blood vessels causes severe pain called “crisis”

Mild to severe, short or long lasting pain to the:ChestStomachLegsArmsBones Joints

Sickle cell anemia also causes damage to the spleen, an increased rate for infection, and stroke.

Sickle cell anemia is an inherited gene. The gene codes for normal HgbA or abnormal HgbS.

If a person inherits 1 normal gene and 1 for sickle cell, they are a carrier (sickle cell trait), show few symptoms of the disease & are able to pass the disease on to their children.

If a person inherits both genes for sickle cell they have sickle cell anemia and show all of the traits.

Autosomal InheritanceHgbA & HgbS are co-dominant

Sickle Cell Inheritance

Sickle Cell RBC’s infected with malaria are destroyed faster than normal RBC’s ↓ the infection.

Evolutionary Concept

Sickle cell trait is an advantage in areas w/ malaria Malaria Protozoan parasites

HBB: Gene Associated w/ Sickle Cell Anemia

Locus: 11p15.5 - HBB gene is found in region 15.5 on the short (p) arm of human chromosome 11. Gene Structure: normal allele for this gene is 1600 base pairs long and contains three exons.mRNA: The intron-free mRNA transcript for the HBB gene is 626 base pairs long. Coding Sequence (CDS): 444 base pairs within the mRNA code for the amino acid sequence of the gene's protein product.

Protein Size: The HBB protein is 146 amino acids long and has a molecular weight of 15,867 Da. See the annotated

Gel Electrophoresis Test for Sickle Cell

HgbS more (-) glutamic acid substituted by less (-) valine, so travels slower towards (+) end

Gel Electrophoresis Virtual LabSort and measure DNA strands by running your own gel electrophoresis experiment. ... See how gel electrophoresis is used in forensics ...learn.genetics.utah.edu/content/labs/gel/ - 7k - Cached - Similar pages -

Try your own virtual gel electrophoresis!

http://learn.genetics.utah.edu/content/labs/gel/