The Genetic Disorder - Paper

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Monifah Cotterell
Block#2
May-4-11

  The genetic disorder that I did is called sickle cell disease, while it is also known by the names sickle-cell anaemia, and drepanocytosis. Sickle cell disease is a disease passed down through families in which red blood cells form an abnormal crescent shape. (Red blood cells are normally shaped like a disc.) The sick cell then decreases it results in a risk of a variety of complications, this all happens because of the mutation in the haemoglobin gene. Hemoglobin is a protein inside red blood cells that carries oxygen. Sickle cell anemia is caused by an abnormal type of hemoglobin called hemoglobin S. Hemoglobin S distorts the shape of red blood cells, especially when exposed to low oxygen levels .The distorted red blood cells are shaped like crescents or sickles. These fragile, sickle-shaped cells deliver less oxygen to the body's tissues. They can also clog more easily in small blood vessels, and break into pieces that disrupt healthy blood flow. In the past, sickle cell patients often died from organ failure between ages 20 and 40. Thanks to a better understanding and management of the disease, today, patients can live into their 50s or beyond. About 1 in 500 African-American children born will have sickle-cell anaemia. Sickle-cell anaemia is the name of a specific form of sickle-cell disease in which there is homozygosity for the mutation that causes HbS. Sickle-cell anaemia is also referred to as "HbSS", "SS disease", "haemoglobin S" or permutations thereof. In heterozygous people, who have only one sickle gene and one normal adult haemoglobin gene, it is referred to as "HbAS" or "sickle cell trait". Sickle cell anemia is inherited from both parents. Sickle cell disease is much more common in people of African and Mediterranean descent. It is also seen in people from South and Central America, the Caribbean, and the Middle East. Someone who inherits the hemoglobin S gene from one parent and normal...