Print Email Download Reference This Send to Kindle Reddit This
submit to reddit

G6pd Deficiency And Gauchers Disease Biology Essay

It is always good to know more about our own bodies, and knowing about this particular type of disease could be very helpful for the future generations. Enzymatic disorders as the name implies are connected to malfunction of enzymes or lack of them or simply a shortage in their number, causing a disorder in the body.

My interest in Biochemistry and the body functions in general led me to this topic. After we understood enzymes in grade 10 I was curious to understand more about them, and here I am presenting you this paper with a small portion of information in the wide field of biochemistry. It is also very useful to know about these things, even though both diseases I will be talking about are genetic, we never know when we have to encounter someone suffering from them. Heck, they could even affect our children, so it’s always good to know.

By the end of this paper I expect to have a better understanding of the 2 diseases, the enzymes responsible for them, the symptoms, and treatment of both of them.

Overview:

Mutations may result in the synthesis of a defective enzyme with reduced activity or in a reduced amount of a normal enzyme. In either case, the consequence is a metabolic block.

Accumulation of the substrate, depending on the site of block, may be accompanied by accumulation of one or both intermediates. Moreover, an increased concentration of intermediate 2 may stimulate the minor pathway and thus lead to an excess of M1 and M2.

Under these conditions, tissue injury may result if the precursor, the intermediates, or the products of alternative minor pathways are toxic in high concentrations. For example, in galactosemia, the deficiency of galactose-1-phosphate uridyltransferase leads to the accumulation of galactose and consequent tissue damage. In phenylketonuria, a deficiency of phenylalanine hydroxylase results in the accumulation of phenylalanine. Excessive accumulation of complex substrates within the lysosomes as a result of deficiency of degradative enzymes is responsible for a group of diseases generally referred to as lysosomal storage diseases.

2. An enzyme defect can lead to a metabolic block and a decreased amount of end product that may be necessary for normal functions. For example, a deficiency of melanin may result from lack of tyrosinase, which is necessary for the biosynthesis of melanin from its precursor, tyrosine. This results in the clinical condition called albinism.

3. Failure to inactivate a tissue-damaging substrate is best exemplified by α1-antitrypsin (α1-AT) deficiency. Patients who have an inherited deficiency of serum α1-AT are unable to inactivate neutrophil elastase in their lungs. Unchecked activity of this protease leads to destruction of elastin in the walls of lung alveoli, leading eventually to pulmonary emphysema

G6PD Deficiency:

The most common of all enzyme disorders is Glucose-6-Phosphate dehydrogenase deficiency. G6PD is a cytosolic enzyme involved in metabolic processes especially those of red blood cells. It functions in the pentose phosphate pathway by supplying reducing energy to cells (Mainly erythrocytes) by maintaining the level of the co-enzyme nicotinamide adenine dinucleotide phosphate (NADPH). NADPH then maintains the level of glutathione in these cells that helps protect the red blood cells-erythrocytes- against oxidative damage.

The lack of activity in G6PD is a disease called “G6PD Deficiency”. The disease is an X-linked hereditary disease. Individuals with the disease may undergo nonimmune hemolytic anemia, that is the abnormal breakdown of red blood cells, in response to a number of causes, most commonly infections or exposure to certain chemicals. G6PD deficiency is also closely linked to favism, a disorder characterized by a hemolytic reaction to consumption of broad beans (Fava is Italian for broad bean). It is common confused that all people with G6PD deficiency suffer from favism, but not all people with G6PD deficiency would develop favism.

Causes:

Mutations in the G6PD gene cause glucose-6-phosphate dehydrogenase deficiency.

The G6PD gene provides instructions for making an enzyme called glucose-6-phosphate dehydrogenase. This enzyme is involved in the normal processing of carbohydrates. It also protects red blood cells from the effects of potentially harmful molecules called reactive oxygen species. Reactive oxygen species are byproducts of normal cellular functions. Chemical reactions involving glucose-6-phosphate dehydrogenase produce compounds that prevent reactive oxygen species from building up to toxic levels within red blood cells.

If mutations in the G6PD gene reduce the amount of glucose-6-phosphate dehydrogenase or alter its structure, this enzyme can no longer play its protective role. As a result, reactive oxygen species can accumulate and damage red blood cells. Factors such as infections, certain drugs, or ingesting fava beans can increase the levels of reactive oxygen species, causing red blood cells to be destroyed faster than the body can replace them. A reduction in the amount of red blood cells causes the signs and symptoms of hemolytic anemia.

Researchers believe that carriers of a G6PD mutation may be partially protected against malaria, an infectious disease carried by a certain type of mosquito. A reduction in the amount of functional glucose-6-dehydrogenase appears to make it more difficult for this parasite to invade red blood cells. Glucose-6-phosphate dehydrogenase deficiency occurs most frequently in areas of the world where malaria is common.

Some symptoms seen are:

Fatigue

Appearing very pale

Sudden rise in body temperature

Headache

Dizziness

Rapid heart beats

Shortness of breath

Pain in the back or abdomen

Urine appears very dark, red, red-brown, brownish or tea colored

Yellow colouring of the eyes and skin (jaundice)

Spleen may be enlarged

The symptoms usually disappear when the offending food or drug is stopped.

Diagnosis of G6PD deficiency

When any of the above mentioned symptoms present themselves in a person of ethnic groups susceptible to the condition then, G6PD deficiency is suspected. In children, most cases go undetected until the child develops a health problem.

Some laboratory investigations asked for are:

Complete blood count: active G6PD shows presence of "Heinz bodies" (protein aggregates) within the red blood cells.

Liver Function Tests: done to rule out other causes of liver damage and jaundice.

Coomb's Test: to check for presence of direct antiglobulin. The results should ideally be negative as RBC breakdown isn't an auto-immune condition.

Haptaglobulin: reduced in RBC breakdown (hemolysis).

Beutler Fluorescent spot test: The conversion of nicotinamide adenine dinucleotide phosphate (NADP) to its reduced form in RBCs is the basis of diagnostic testing for the deficiency.

Treatment of G6PD deficiency

For the majority of people affected, treatment of G6PD is as simple as avoiding the triggering agent. Severely ill children may need hospitalization, oxygen support and intravenous fluids.

It is important to avoid the foods and drugs below.

Antibiotics (Sulphonamides, Co-trimoxazole (Bactrim, Septrin), Dapsone, Chloramphenicol, Nitrofurantoin, Nalidixic acid,

Antimalarials (Chloroquine, Hydroxychloroquine, Primaquine, Quinine, Mepacrine )

Chemicals (Moth Balls, napthalene, Methylene blue

Foods (Fava beans - also called broad beans)

Other drugs (Aspirin, Phenacitin, Sulphasalazine, Methyldopa, Large doses of vitamin C, Hydralazine, Procainamide, Quinidine, Some anti-cancer drugs )

Gaucher’s Disease:

Gaucher’s Disease is a genetic disease in which a fatty substance (lipid) accumulates in cells and certain organs. Gaucher's disease is the most common of the lysosomal storage diseases. It is a form of sphingolipidosis (a subgroup of lysosomal storage diseases), as it involves dysfunctional metabolism of sphingolipids. The disorder is characterized by bruising, fatigue, anemia, low blood platelets, and enlargement of the liver and spleen. It is caused by a hereditary deficiency of the enzyme glucocerebrosidase. The enzyme acts on the fatty acid glucosylceramide. When the enzyme is defective, glucosylceramide accumulates, particularly in white blood cells, most often macrophages (mononuclear leukocytes). Glucosylceramidase can collect in the spleen, liver, kidneys, lungs, brain and bone marrow.

Symptoms: Symptoms may include enlarged spleen and liver, liver malfunction, skeletal disorders and bone lesions that may be painful, severe neurologic complications, swelling of lymph nodes and (occasionally) adjacent joints, distended abdomen, a brownish tint to the skin, anemia, low blood platelets and yellow fatty deposits on the white of the eye (sclera). Persons affected most seriously may also be more susceptible to infection. Some forms of Gaucher's disease may be treated with enzyme replacement therapy.

Causes: The disease is caused by a recessive mutation in a gene located on chromosome 1 and affects both males and females. About 1 in 100 people in the United States are carriers of the most common type of Gaucher disease. The carrier rate among Ashkenazi Jews is 8.9% while the birth incidence is 1 in 450.

The disease is named after the French doctor Philippe Gaucher, who originally described it in 1882.

Disease Classification

Gaucher disease is divided into two major types—neuronopathic and non-neuronopathic disease—based on the particular symptoms of the disease. In non-neuronopathic disease most organs and tissues can be involved, but not the brain. In neuronopathic disease the brain is also involved.

Non-neuronopathic disease - Type 1 Gaucher disease

Type 1 Gaucher disease is the most common form of the disease and does not involve the central nervous system; therefore, it is also called non-neuronopathic. Although Type 1 Gaucher disease is sometimes referred to as ‘adult Gaucher disease’, it can affect individuals of all ages,  and in hindsight, most Type 1 patients acknowledge that their first symptoms started before adulthood. 

Type 1 Gaucher disease has a particularly wide variation in clinical signs, symptoms and disease course. In some cases, the symptoms may begin in childhood and rapidly worsen over time. In other cases, the first symptoms may only be noticed well into adulthood. There are even cases of people who are shown to have a glucocerebrosidase gene defect, but who do not show any symptoms. In general, the earlier in life the first symptoms appear, the more likely it is that the disease will be severe and will progress rapidly if left untreated.

Perhaps the most common sign of Type 1 Gaucher disease is an enlargement of the spleen. Spleen enlargement is often the initial finding and may be first recognized when a child is young. Skeletal symptoms of bone involvement can occur at any time in life, both in children and the elderly. Skeletal abnormalities are also very common and they are present in the majority of patients at the time of diagnosis.

Neuronopathic Gaucher disease

If brain function is affected in Gaucher disease, it can appear early in life and progress rapidly as with acute neuronopathic or Type 2 Gaucher disease; or it can appear more gradually and worsen over time, as with Type 3 or chronic neuronopathic Gaucher disease.

Type 2 Gaucher disease

Type 2 Gaucher disease is a very rare, rapidly progressive form of the disorder that affects the brain as well as the organs affected by Type 1 Gaucher disease. Formerly called ‘infantile Gaucher disease’, Type 2 is characterized by severe neurological involvement in the first year of life. Fewer than 1 in 100,000 newborns have Type 2 disease. This form of Gaucher disease does not appear to be concentrated within any particular ethnic group. Infants with Type 2 disease typically appear normal during the first few months of life before developing neurological signs and many of the symptoms associated with Type 1. An afflicted child usually does not live past the age of 2 years, due to the severe involvement of the brain.

Type 3 Gaucher disease

Formerly called ‘juvenile Gaucher disease’, Type 3 is characterized by a slowly progressive brain involvement, in addition to severe disease of the other organs typically affected by Gaucher disease. Type 3 Gaucher disease is also very rare. While not limited to any particular ethnic group, a concentrated number of cases have been reported in Sweden and a higher number of cases have been reported than in the general population in Spain and Japan. 

Conclusion

We have come to the understanding that a lack of enzymes caused by genetic malfunction could cause severe disease that could eventually cause someone their life. But on the bright side, research and close study of the diseases can eventually limit the spread of the disease or eliminate it altogether.

We also learned that both G6PD deficiency and Gaucher’s disease are related to metabolism, the first affecting the red blood cells, and the latter affecting the metabolism and digestion of fatty substances.

Print Email Download Reference This Send to Kindle Reddit This

Share This Essay

To share this essay on Reddit, Facebook, Twitter, or Google+ just click on the buttons below:

Request Removal

If you are the original writer of this essay and no longer wish to have the essay published on the UK Essays website then please click on the link below to request removal:

Request the removal of this essay.


More from UK Essays