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Hereditary diseases result in some of the worst effects to human health. This paper seeks to utilize a media source in the description of thalassemia.
This refers to inherited autosomal recessive blood diseases. In thalassemia, the two copies of the concerned gene undergo mutation. The conditions can also be referred to as “Mediterranean anemia, Jaksch anemia or Cooley’s anemia” (Deepa 2010). This group of disorders leads to similar clinical manifestations in patients. A defect in alpha and beta chains of hemoglobin is the common underlying abnormality in thalassemia (Deepa 2010). Anemia that is “linked to the alpha chain is referred to as alpha thalassemia while that which is linked to a defect in the beta chain is referred to as beta thalassemia” (Leung, Lau, & Chung 2009). The defects can further be classified into thalassemia major, which describes the homozygous type and thalassemia minor which is the heterozygous form. Individuals with thalassemia have a reduced ability to synthesize one of the globin chains that constitute hemoglobin (Deepa 2010). Thus resulting in the production of defective hemoglobin molecules that cause anemia (Tassiopoulus & Deftereos 2005). “Different types of anemia are can result and the type and number of genes that are affected will often determine the severity of the anemia” (Deepa 2010). Generally, patients who are suffering from this condition lack the capacity to produce enough and efficient red blood cells. If the patient has to survive, then red blood transfusion intervention is carried out every 2-3 weeks (Deepa 2010).
This form of thalassemia occurs when a mutation in the genes of the hemoglobin molecule leads to reduced synthesis of alpha globulin chains (Tesoriere, Allegra, Butera, & Gentile 2006). The defect is diagnosed by the detection of double alpha globulin chain genes on both sixteenth chromosomes. This totals to four genes instead of the usual two. The alpha chain forms a vital component of both “the fetal hemoglobin A which is synthesized before birth and hemoglobin A2 that is present after birth” (Deepa 2010). Alpha thalassemia is often identified in the parent after the birth of a child suffering from the condition (Deepa 2010). In extreme cases, alpha thalassemia will result in still birth.
Alpha thalassemia can be divided into four types: First, the carrier state; individual is regarded as an alpha thalassemia carrier when he or she possesses the genes but does not have the symptoms (Leung, Lau, & Chung 2009). In the carriers, two alpha chain genes are deleted. A ‘Cis deletion’ results in the elimination of two alpha chain genes on one of the two chromosomes 16 (Deepa 2010). A ‘trans deletion’ results in the deletion of one of the alpha genes on each of the chromosome 16 (Leung, Lau, & Chung 2009). Every pregnancy in parents who are carriers of a Cis there is a 25% probability of getting child with alpha thalassemia major. DNA analysis is used to distinguish between the carriers of the two types of deletions. Second, Hemoglobin H disease; this condition results when an individual possesses only one functional alpha chain gene (Tassiopoulus & Deftereos 2005). This implies that three alpha chain genes are deleted in the two chromosomes. The anemia that results from this type of deletion is referred to as alpha hemolytic anemia. Individuals with this disorder have an increased chance of getting children with alpha thalassemia major as they possess only one chromosome 16 that has a Cis deletion (Deepa, 2010). The third form is referred to as alpha thalassemic major. “This condition often results in the death of the fetus in the uterus as all the four alpha chain genes on chromosome 16 are deleted” (Deepa 2010).
Instances of alpha thalassemia can occur anywhere in the world but the following regions are more prone: “Africa, Middle East, India, South East Asia and southern China and in the Mediterranean region” (Leung, Lau, & Chung, 2009, pp. 30).
Various tests are conducted to investigate alpha thalassemia. These tests include: “Complete blood change (CBC) which refers to the measurement of the size, number and maturity of different cells in a particular volume of blood” (Deepa, 2010). The second test that can be conducted in the investigation of alpha thalassemia is hemoglobin electrophoresis with A2 and F quantition (Leung, Lau, & Chung 2009). This is a laboratory technique that is used to establish the types of hemoglobin in the individual’s blood. Another test that is normally conducted is FEP (Free Erythrocyte protoporphyrin) and Ferritin (Deepa 2010). This test is conducted to eliminate iron deficiency anemia in the course of diagnosis. The above tests can be carried out on a single blood sample. Prenatal testing is conducted using samples that are drawn from the chorionic villus (Leung, Lau, & Chung 2009).
This form of “thalassemia is often caused by a mutation in the beta globin chains” (Deepa 2010). In the human body, chromosome 11 is often concerned with the regulation of beta proteins. The synthesis of a beta globin protein chain is facilitated by two genes, in the case one or both genes are mutated then the individual will present with beta thalassemia (Tesoriere, Allegra, Butera, & Gentile 2006). In the event that the two genes undergo mutation then the affected person will have either “beta thalassemia intermediate or beta thalassemia major (Deepa 2010). The intermediate results in moderate anemia while the major leads to severe anemia” (Tesoriere, Allegra, Butera, & Gentile 2006).
“Beta thalassemia can be manifested in three conditions: Beta thalassemia minor or trait in which a mutated gene is inherited and does not show symptoms” (Deepa 2010). The second is beta thalassemia intermediate which represents a condition that lies between major and minor thalassemia (Leung, Lau, & Chung 2009). Patients suffering from this condition have hemoglobin of 7-9g/dl and they require blood transfusion when the hemoglobin level goes down during infection of when under stressful conditions (Deepa 2010). The last type, beta thalassemia major is where by a child is born normal but later develops anemia in the initial year. “The condition may result in growth failure, deformities, enlarged liver and liver among other indications” (Deepa 2010). This condition often requires “intensive medical intervention which may consist of 2-3 weekly transfusions, desferrioxamine injections for 8-12 hours at home” (Tesoriere, Allegra, Butera, & Gentile 2006). To diagnose beta thalassemia, a basic blood test referred to as is hemoglobin electrophoresis is required. In the course of pregnancy, the fetus can be diagnosed using the following tests: “CVS (8-10 weeks), aminiocentesis (14-18 weeks) and fetal blood testing (18-20 weeks)” (Deepa 2010).
Thalassemias are serious medical problems that posses a great risk to the health of the individual. Proper diagnosis should be conducted to determine whether the fetus is has the condition and appropriate medical intervention taken to control the effects. The above description provides sufficient and accurate information on the causes and intervention methods for thalassemia. If the guide lines are followed by practitioners then a lot can be achieved in the detection and management of thalassemia.
Deepa, P. (2010). Genetic Disorder – Thalassemia. Ezine Articles, Web.
Leung, T., Lau, T., and Chung T. (2009) Thalassaemia screening in pregnancy. Current Opinion in Obstetrics & Gynecology , 17 (2), pp. 129–34.
Tassiopoulus, S., and Deftereos S. (2005) Does heterozygous beta-thalassemia confer a protection against coronary artery disease? Annals of the New York Academy of Sciences , 1054, pp. 467–70.
Tesoriere, L., Allegra, M., Butera, D., and Gentile C. (2006) Cytoprotective effects of the antioxidant phytochemical indicaxanthin in beta-thalassemia red blood cells. Free Radical Research , 40 (7), pp. 753-61.