Genetic Mutation Of A Single Nucleotide Base

Sickle Cell Disease is an autosomal recessive genetic disease that occurs due to a mutation in the β-globin gene of hemoglobin. Autosomal meaning that it is not linked to a sex chromosome, so either parent can pass on the gene to their child. This mutation is a result of a single substitution of amino acids, Glutamic for Valine at position 6 of a β globin chain. The presence of this mutation causes

SCDAAMI population includes all patients with SCD or trait from infancy to 21 year-old and their families.

Then the sickle cell allele frequency HbS will survive and have an increased frequency while HbA allele frequency will decrease.

These mutations can be due to an error in DNA replication or due to environmental factors, such as cigarette smoke and

Resulting in lack of blood flow to the region most commonly in the peripherals and organs causing pain in hands, feet, joints, fever and in severe forms develops in bones (Smeltzer, Bare, Hinkle, & Cheever, 2010). Sickle cell anemia is the most severe form of SCD, lesser forms include sickle cell hemoglobin C disease, sickle cell hemoglobin D disease, and sickle cell beta-thalassemia. (Smeltzer, Bare, Hinkle, & Cheever, 2010). . The term sickle cell trait is referred to people who are carriers of certain strand of abnormal gene, and it is a type of benign state of sickle cell hemoglobin C (Smeltzer, Bare, Hinkle, & Cheever, 2010). Though, if two people with the same traits may have child, the child will have a 1 in 4th chance of receiving two abnormal genes will develop sickle cell anemia (Smeltzer, Bare, Hinkle, & Cheever, 2010).

The blood protein in Methemoglobinemia are unable to carry oxygen, which makes it harder for the tissue to get the amount of oxygen

Sickle Cell disease also known as SCD is a genetic disease of a person’s red blood cells. The shape of a normal person’s RBC is shaped like a disk. This shape of the red blood cells allows for the flexibility that helps the cells move through blood vessels.

As mentioned earlier, SCD is Autosomal recessive, which means both copies of the sickle gene are inherited from the parents (Sickle Cell Disease). Those more likely to present with Sickle Cell Disease are of African, Mediterranean, and Caribbean origin (Sickle Cell Disease). Genes that SCD can carry in hemoglobin are as follows: Hemoglobin SS(hgbSS), Hemoglobin SC (hgbSC), Hemoglobin Sβ° thalassemia, hemoglobin Sβ°+ Thalassemia, Hemoglobin SD(hgbSD) and Hemoglobin SE(hgbSD) (What is Sickle Cell Disease?). Below is a case study about the Orca Family that shows family generations of SCD and the Sickle Cell

As explained by Dr. Richard Weisiger, bilirubin is produced during the breakdown of Hgb and other hemoproteins, and it is filtered out by the liver. Hyperbilirubinemia occurs when the liver cannot filter the bilirubin from the blood fast enough and the bilirubin is absorbed into tissues causing jaundice.

The genetic disorder I will be discussing is Sickle Cell Disease. Sickle Cell Disease is an inherited blood disorder. Children who have this disease have two defective hemoglobin S genes, which they receive one from each parent. This gene occurs in chromosome 11. The sickle cell gene is passed from generation to generation in a pattern of inheritance called autosomal recessive inheritance. This means that both the mother and the father must pass on the defective form of the gene for a child to be affected. If only one parent passes the sickle cell gene to the child, that child will have the sickle cell trait.

One drug, hydroxyurea, appears to decrease expression of the mutant beta globin gene even as it increases the expression of fetal hemoglobin genes, whose proteins can substitute for the hemoglobin beta chain. Beyond hydroxyurea, other treatments for SCA are still in the preliminary stage. One idea is to remove stem cells from the patient's bone marrow, insert healthy beta globin genes, and then transplant these genetically engineered cells back into the patient. Bone marrow transplants have met with occasional success; however, the procedure carries several major risks, especially graft versus host disease (GVHD). Also, finding compatible bone marrow donors in the African-American community is often

cells are sickle shaped and are very hard which tend to get stuck in small blood

When bonds between the alpha subunits are strengthened and rotation to the relaxed structure is prevented the oxygen affinity is usually decreased. A process called the Bohr effect is completed with in the heamoglobin, this process is a result of CO2 from the tissues being released into the blood, the blood is acidified by the increase in hydrogen ions resulting in heamoglobins oxygen affinity to be decreased (Keates, 2004). The theory behind the Bohr effect is that, compared to the relaxed structure hydrogen is bound to heamoglobins tense structure more effectively (Keates, 2004). CO2’s effect on heamoglobin is similar but it tends to bind to the alpha globins Nterminus. The uptake of CO2 is facilitated by the release of oxygen in tissues by the tense structure as the CO2 binds to the tense structures globin better. When the heamoglobin carries the CO2 back into the lungs, the oxygen in the lungs causes the heamoglobin to switch to the relaxed structure, causing the CO2 to be released into the lungs (Keates,

In people of West African ancestry such as the man in the study typically have SCD/haemoglobin C disease. This is a type of SCD that results from the inheritance of one HbS gene through one gene for HbC and this type of SCD is the most common abnormal haemoglobin gene in West Africa. The inheritance pattern for SCD is not complicated because if both parents hold one abnormal gene, there is a 1 in 4 possibility that any offspring will

Essentially, there is an incorrect base- pair change when the Deoxyribonucleic Acid strand are being duplicated, exchanging the “the sixth amino acid from glutamic acid to valine causing the mutated hemoglobin (HbS) to polymerize” or change the shape of each cell (Adams1). The most severe form of Sickle Cell Disease is Hemoglobin SS, in which both parents are carriers of Sickle Cell gene, “SS”, and ultimately reproduce a child that has SCD. In Hemoglobin SC, one parent has the gene “S” while the other has the trait “C”, thus having a milder form of Sickle Cell Disease (Stuart7). Sickle Cell Anemia or Hemoglobin S beta thalassemia is another form of SCD, where one parent has the “S” gene while the other parent has an additional form of anemia or thalassemia (CDC5). Due to the constricting shape of the erythrocytes, the blood cells began to die at an alarming rate causing the body to be deprived of oxygen, creating a number of other health complications. Stroke, neurocognitive functions, infections and the increased risk of death can occur if left untreated. Amongst individuals with SCD, the risk of having a stroke is increased, especially in children (Adams1). Stroke is said to be caused by the constriction of blood vessels and lack of oxygen in the brain that is associated with Sickle Cell Disease. However, because of the stroke increase in