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Sickle Cell: What is it? • 3 distinct types o Sickle Cell Anemia o SC Disease o S-Beta Disease • Caused by a mutation in the beta globin (protein of the blood) • That mutation causes change in the shape and overall behavior of the blood cells • “sickle, stiff, and sticky” RBC’s can cause severe organ damage and intense pain • One of the most common GENETIC disorders in the U.S. o 1/375 African American babies get it

Cause: • Beta Globin proteins are in the RBC • Purpose is to carry heme; a molecule • Beta and Alpha globin combine and form hemoglobin o Molecule that carries oxygen to the cells o One molecule of hemoglobin consists of 2 beta and 2 alpha and a heme group • Heme of each group binds the oxygen molecule • On chromosome 11, how to make beta globin inside a gene there. o 2 11 chromosomes=2 beta globin

• The Mutation: o The code inside the beta globin genes is GAG near the front of the code. The mutation changes it to GTG. o GAG usually tells the protein “machine” to put a glutamate amino acid into the protein o The new code tells it to put valine in • Valine: When oxygen is released by the molecule the valine becomes sticky to nearby V-shaped notch in the hemoglobin • The valine causes those notches to, when they come closer, stick together and form a “hemoglobin polymer” • The longer the polymer the more it stretches the RBC into the shape of a sickle or a banana • The cell can only change back when it gets to the lung and takes in more oxygen • That goes on for a while until the cells retain the sickle shape • After 10-20 days the cells die  Because of the death of the cells anemia kicks in. • Lowers amount of oxygen delivered to the bodie’s tissues • Causes fatigue • Shortness of breath • As those sickle cells pile up they cause a clot and the regular RBC’s can’t fit through and because of such the tissue dies and causes severe pain for a while

How is it inherited? • Sickle Cell Anemia is inherited but not contagious • Inherited if you receive each S-type beta globin gene from your parents

• SC- o Inherit S-type from one and C type beta globin gene

• S-Beta o Inherits S-type from one and Beta type beta globin gene from another • B genes produce little to know beta globin • It can be passed if both parents have a S gene. The child has a 25% chance of getting it. Same for SC and S-Beta