What are the Prospects for Genetic Therapies for Polycythaemia?
Polycythaemia is a blood disorder defined as an increase in blood erythrocyte concentration. Absolute polycythaemia is where this increase is caused by greater erythrocyte production, determined by measuring the haematocrit level, with one study showing that 83% of sufferers have a haematocrit level of >55%. This should not be confused with relative polycythaemia, caused by a decrease in blood plasma volume often secondary to hypertension. Interestingly, those affected tend to also have increased blood platelet and white cell concentrations, which correlates well with the notion that the disease is caused by a genetic defect in the haematopoietic stem cell population within the bone marrow. Studies have shown the median age of onset to be 60, although a Mayo Clinic study in Olmstead County, Minnesota showed it to be slightly higher, at between 70 and 79 years, with men affected more than women – though the reason behind the gender inequality is currently unknown. In addition, its prevalence within the US is thought to be in the region of 50/100,000. Furthermore, it has long been known that Finnish skier and seven time Olympic champion Eero Mantyranta suffered from the disease, and it is often stated that his success, at least in part, can be put down to his polycythaemia – indeed experiments have shown that it can increase the blood oxygen carrying capacity by up to 50%, an undeniable asset to any endurance athlete. However, the disease can also prove fatal in many cases because the thickened blood increases the probability of clot formation, giving deep vein thrombosis and potentially pulmonary embolus. It is this double edged nature of polycythaemia that first took ...
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...there are many techniques available that have the potential to treat the disease. If the mutation is somatic, the use of embryonic stem cells taken from you at birth seems promising (though currently taking umbilical cord stem cells is not done clinically) – alongside the possibility of using induced pluripotent stem cells instead. If the mutation is inherited, the use of viral DNA vectors carrying micro RNA that down regulates JAK2, TET2 or HMGA2 also seems promising, though perhaps using lipid-based nano particles is more of a realistic goal for this research due to the difficulty of not injecting the DNA in such a way that it affects the functions of other genes. For both acquired and inherited mutations giving polycythaemia, therapies which revert point mutations seems interesting, but more research needs to be done to understand the exact mechanisms of action.
Vitamin B12 deficiency limits selenium methylation and excretion resulting in higher tissue selenium levels and subsequent toxicity. It occurs in people whose digestive systems do not adequately absorb the vitamin from the foods they eat. Vegetarians who eat eggs and milk products are the most at risk because, on average, they consume less than half the adult vitamin B12 Recommended Dietary Allowance (RDA) while strict vegans (who don't eat any animal products, including meat, eggs, or milk) are at an even greater risk. Vitamin B12 is important since it works with the vitamin folate to make the body’s genetic material and help keep levels of the amino acid homocysteine in check which helps to decrease heart disease risk. It is also essential in the production of red blood cells which carry oxygen through the blood to the body’s tissues. Life Extension gives offers some of selenium supplements. Babies who are born of parents with low selenium and vitamin B12 rich foods are at risk of anaemia.
This essay will explain the hormone Erythropoietin, its effects and its role in the professional sporting industry. Explaining what Erythropoietin is, the process Erythropoiesis, its role in the body, its side effects vs. benefits and its role in modern sport will form the basis of this essay. By the conclusion of this essay my point of view will be that naturally occurring Erythropoietin is integral to homeostasis and synthetic Erythropoietin should only be used for specific medical conditions rather than as a performance enhancer in professional sport.
Gene therapy is the application of the technique where the defect-causing "bad" genes are replaced by correct "good" genes. The idea of gene therapy is to treat the disease by correcting the "bad" DNA (Deoxyribonucleic acid) rather than the current me thod of providing drugs, or proteins not produced by the defective gene. Gene therapy addresses the problem first hand by directly working with the genetic information causing the disease. From the book Shaping Genes, Dr. Darryl Macer says "It is like f ixing a hole in the bucket, rather than trying to mop up the leaking water." There are two kinds of gene therapy, somatic cell gene therapy and germline gene therapy.
Tuberculosis or TB is an airborn infection caused by inhaled droplets that contain mycobacterium tuberculosis. When infected, the body will initiate a cell-mediated hypersensitivity response which leads to formation of lesion or cavity and positive reaction to tuberculin skin test (Kaufman, 2011). People who have been infected with mycobacteria will have a positive skin test, but only ones who have active TB will show signs and symtoms. Basic signs and symptoms include low grade fever, cough with hemoptysis, and tachypnea. They may also show pleuristic chest pain, dyspnea, progressive weight loss, fatigue and malaise (Porth, 2011).
There have been four somewhat recent successful gene therapy treatments. The four deal with correcting hemophilia, bone marrow transplants, skin cancer, and vessel growth. In the success with the bone marrow transplants, French researchers collected bone marrow cells from patients, used gene therapy to correct the bone marrow, and then returned the bone marrow to the patient. This was 80% successful as reports 16 months after the transplants showed. Squamous cell carcinoma, skin cancer of the head and neck, was treated using gene therapy as well. The fourth trial was where DNA was used to carry a substance that stimulates blood vessel growth to damaged heart tissue and in this trial there was much success noted.
The diminished rate of synthesis amongst the globin chains was first described from Cooley and Lee. However, the term “Thalassemia: was coined by Whipple and Bradford in 1936 (Bain, 2006). The term “Thalassemia” is derived from the Greek words “Thalassa” (sea) and “Heama” (blood) and refers to disorders associated with defective synthesis of the alpha or beta globin subunits of the hemoglobin molecule. Hemoglobin A (a2B2) is inherited. ...
Scientists are also studying gene therapy as a good treatment for sickle cell anemia. One day, doctors may be able to stop the disease by changing or replacing the abnormal gene that causes sickle cell anemia.
Before WWI, the practice of medicine was far from how it has developed into today. The practice was not advanced, and therefore, had few concrete methods. However, with the beginning of the First World War, there was a great push to improve these methods. Although the war caused much illness and death, it also catalyzed many improvements such as blood transfusions, x-rays, vaccines, and sanitation.
There are many causes of anemia in the body. Some factors include genetics and deficiencies in the diet. Ms. A claims that for the past 10 – 12 years menorrhagia and dysmenorrheal have been a problem for her. Menorrhagia is abnormal and heavy menstrual bleeding during menstruation (Mayoclinic, 2013). Menorrhagia can deplete iron levels in the blood and increase the risk of an individual to have iron deficiency anemia. This is the cause of Ms. A’s anemia. Moreover, Ms. A says that she constantly takes aspirin especially in the summer to prevent stiffness in the joints. Aspirin affects and hinders the production of red blood cells (Mayoclinic, 2013). From the description of anemia given above, the lack of red blood cells, leads to low levels of iron and therefore low levels of hemoglobin which in turn affects the transportation of oxygen and thereby causing shortness of breath. Ms. A’s initial complains of shortness of breath and fatigue is the reason why she went to see the physician.
In most cases becoming pregnant brings happiness and excitement to the eager partners. Imagine showing up at a hospital, rushing, with all hopes of bringing another life into this world to only figure out that there was no baby in the first place. How would one feel devastated, hurt, depressed? Some women imagine she is pregnant, but soon finds out that the symptoms are not caused by a fetus but by a disorder called pseudocyesis. Pseudocyesis is a psychological disorder where the mind tricks the body and causes the female body to have symptoms of a pregnant woman. A women with this disorder have similar symptoms to a lady that is carrying a child; meanwhile, others have the exact same symptoms excluding the unborn. Some of the symptoms are swollen belly, enlarged breast, and sensations of fetal movement. One who feels the need to become impregnated, due to infertility, and miscarriages can cause ones body to fabricate indications of a pregnancy. Pseudocyesis can make a woman change mentally and physically; therefore, these changes can cause one to have depression, anxiety, and psychological disorders.
Vitamin B12 is an essential nutrient that plays an important role in DNA synthesis and nerve function. It is contained in high amounts in animal derived foods such as milk, eggs, and meat. The vitamin is stored in the liver long-term. Individuals with vegetarian, vegan, or other forms of restricted diet may develop the condition after approximately 6 months as liver stores of vitamin B12 become depleted. Some individuals develop the condition due to autoimmune destruction of cells in the stomach that produce intrinsic factor. Intrinsic factor is necessary for proper absorption of vitamin B12 in the small intestine.
EPO is produced naturally in the body, primarily by the kidneys however the EPO injection is a man-made version designed produce red blood cells by stimulating bone marrow. The intended use of EPO is primarily for patients with later stage kidney disease or severe anemia. Blood transfusions are another method highly used and there are two kinds, Autologous and homologous. An autologous blood uses the athletes own blood, which has been previously stored until needed. Homologous transfusions are blood transfusions from blood from someone other than the athlete but that has the same blood type. Clinically blood transfusions are given to patients who have lost large amounts of blood due to surgery or injury but can also be given to patients who have low red blood cell counts due to other conditions and illnesses. The final method of blood doping is by the use of synthetic oxygen carriers. Synthetic oxygen carriers are chemicals or purified proteins that have the ability to carry oxygen through the body. The two main synthetic oxygen carries used are HBOCs (hemoglobin-based oxygen carriers and PFCs (perfluorocarbons). Synthetic oxygen carriers are very important in the normal medical setting. They are often used when a patient needs a blood transfusion but there isn’t a blood type match or human blood available. Although the methods are very different from one another the end result to the athlete is the
Genes are made of DNA – the code of life (Gene Therapy- The Great Debate!). The changes in genes may cause serious problems, which we called genetic disorder. In theory, the only method to cure genetic disorders is gene therapy, which basically means the replacement of genes in order to correct the loss or change in people’s DNA. Although gene therapy gives patients with genetic disorders a permanent cure, it is controversial because it has safety and efficacy problems, and raises ethical issues.
proactive measures against recurrence and relapse of the disease can be made. Molecular medicine in genetics will also improve the design and testing of new drugs.
There are several different types of anaemia with different symptoms and effects on the human body most of them have very similar impacts on health. Some people inherit the disorder whilst some grow into it. It can be diagnosed at the age of two or during the younger years in a humans life. The causes of this disorder begin with during pregnancy. Some of the common types of anaemia is: