The most common 'single gene defect' in man comprises primarily of the inherited hemoglobin disorders. These hemoglobinopathies (blood or hemoglobin disorders) together, also have the highest incidence of prevalence worldwide in terms of incidence of single gene disorders.
This classification is based on the type of globin chain (alpha or beta) which is affected. This clearly indicates that hemoglobin structure is central to the pathology of thalassaemia. Beta thalassaemia or Cooley's anemia as it is called refers to decreased beta chain production and hence deficits in hemoglobin due to defects in the gene forming the chain
Hemoglobin (Hb) is protein responsible for oxygen carrying in the body. It is made of four peptide chains, two alpha or a chains and two beta or b chains. Hemoglobin synthesis is controlled by genes which are switched on and off at different phases in the human life (beginning at the embryonic stage). Gamma genes regulate formation of fetal hemoglobin, which is switched to beta genes postnatally. It is about the 9th gestational week that the transcription switch from g chain to b chain production starts. Normally fetal hemoglobin synthesis declines gradually during this time but continues until 9 months of age. It is at about the 9th month after birth that the switch is completed.(Sarnaik 2005). This beta gene therein controls beta chain production in adults.
In patients suffering from beta thalassaemia, there is a switch from a normal gamma-globin gene, in the fetus to an abnormal beta-globin gene, in the adult. (Blau 1994). ...
tations have been described so far) Beta-thalassaemia major is hence a result of transmission of the mutated form of beta-globin gene from both parents, to the offspring. This results in inheritance of both defected form of the gene and has severe clinical manifestations for the patient.
Clinical features and abnormalities
As has been described above, beta thalassemia major refers to a decreased production of beta globin chains which are required for formation of normal haemoglobin in the blood. This results in decreased levels of normal haemoglobin(A) in the body. Interestingly there are evidences of increased levels of fetal (F) and abnormal haemoglobin (A2). Recent studies established that this abnormal increase in other Hb forms was due to production of excess of alpha chains, some of which are consequently utilized to synthesize hemoglobins which do not require beta chains, such as hemoglobin F (a2 g2) or hemoglobin A2 (a2 d2) and hence the elevated levels of such hemoglobins! (Perrimond 2001). Clinically this is very relevant as it leads to excessively reduced RBC life, this is primarily due to precipitation of free alpha chains on the RBCs.
Other clinical features are is extremely severe hypochromic anemia as a result of ineffective erythropoesis. There is also significant decrease in hemoglobin content per cell and microcytosis. In order to compensate for this the body attempts to increase the red cellproduction. This results in increase marrow cavities and 'extramedullary erythropoeisis' in the liver and spleen. The consequences of such endeavours may result in hepatosplenomegaly, bone defects and much discomfort (pain) in patients. In children, there is high incidence of growth deficit, cardiac problems and jaundice (due to excessive break down of red ...
Cite this document
(“Beta thalassaemia major Essay Example | Topics and Well Written Essays - 1500 words”, n.d.)
Retrieved from https://studentshare.net/miscellaneous/272983-beta-thalassaemia-major
(Beta Thalassaemia Major Essay Example | Topics and Well Written Essays - 1500 Words)
“Beta Thalassaemia Major Essay Example | Topics and Well Written Essays - 1500 Words”, n.d. https://studentshare.net/miscellaneous/272983-beta-thalassaemia-major.
There are many types of anemia with different causes and manifestations. Although there are many classifications of the condition, the one based on major pathophysiological characteristics gives three major categories and they are easier to understand than others.
The beta coefficient is like a share's market sensitivity pointer. For instance, if the average rate of return on the stock market rises or falls by 10 per cent, how does the rate of return on an individual share react If the share's rate of return similarly rises or falls by 10 per cent in exact harmony with the market, then one says that the share has a beta coefficient of 1.0; it is just as risky as the 'average' shares in the market.
According to the British Heart Foundation, beta-blockers block the action of certain hormones (i.e., adrenaline) that increase the rate and force of heartbeat. In detail, the blockade of beta-1 receptors slows down the heart rate, reduces myocardial contractility, and lowers systemic blood pressure and it reduces oxygen supply also.
Money swings in the market, when financial crises arises in company, how financial needs are managed viz., in stock market most probably finance inflation may rise or fall and at the same time company's share market also fluctuates that may effect bank interest rate.
The author of the paper states that the Gods clearly do not defend anyone – which is, in brief, the answer to the question “Why does Cordelia die?” It is the ultimate cruelty in a cruel play. The worst can, and does, happen. It is a world without justice, nor any convincing sense of meaningful moral order.
Patients affected by SCD need red blood cell transfusions on a regular basis to reduce morbidity and mortality. The transfusions are administered intermittently to control or prevent a serious complication of SCD, and as a perioperative measure. Or, as a chronic
To achieve a high level of suspense in Psycho, Hitchcock employs several film techniques, which include cinematography, lighting false suspense and scary music. This write up will analyze the three techniques that Hitchcock used to create suspense in Psycho film.
The syndromes of β-thalassaemia result from nucleotide deletions or substitutions in sets of intact genes.
Classification of thalassaemias usually depends on the globin chain type with reduced synthesis. There are four different classes of α-thalassaemia. There is the