Pancreatic Cancer
Pancreatic Cancer is the fourth highest cause of cancer related deaths in the United States. Pancreatic Cancer happens when the cells in the pancreas start to grow uncontrollably and then are not able to die off. The pancreas is a six inch long organ that is located right behind the stomach. There are a couple different ways Pancreatic Cancer forms: Genes are one of them where there can be a mutation or a damages gene which would cause the cells to start to rapidly grow to where they over power everything in the pancreas. There are four different genes that that can be affected to result in this type of cancer, they are oncogenes which tell the cells when to divide, tumor suppressor genes which tell the genes when not to divide, suicide genes which tell the cells to kill themselves if something is wrong, and DNA- repair genes which tell the cells to repair themselves if they are damaged. The gene mutations occur on Chromosome 12 which is the K-ras gene that tells the cells to grow , Chromosome 9, which is the p16 gene that tells a protein to enter the S phase of the cell cycle, Chromosome 17, which is p53 controls the cells that are important to the cell cycle and DNA repair, and Chromosome 18, which is DPC4 this gene is inactivated in 55% of Pancreatic Cancer but it is a protein that is very important in growth of the cell.
Leigh Syndrome
Leigh syndrome is a rare, genetic disease, for which there is no cure, that usually ends in death within two to three years from birth. Leigh syndrome is usually inherited when both parents genes carry a mutation in nuclear DNA. A smaller percentage of people with Leigh syndrome inherited the disease from maternal inheritance. Since mitochondrial DNA (mtDNA) is only inherited from egg cells, both male and females can be affected by Leigh syndrome, but a father cannot pass down traits in the mtDNA. mtDNA is responsible for producing several enzymes important to the production of ATP. Leigh syndrome causes a deficiency of an enzyme called, pyruvate dehydrogenase. Pyruvate dehydrogenase catalyzes the oxidation of pyruvate into acetyl-CoA, which has to first happen in order for the krebs cycle to begin. Leigh syndrome is caused by a genetic mutation in nuclear DNA, SURF1 is the specific gene mutation on the long arm of chromosome 9. Leigh syndrome prevents the mitochondria from carrying out oxidative phosphorylation, the production of ATP. When the cell no longer has an energy source, it cannot function properly and dies.
Tay-Sachs Disease
Tay-sachs disease is a genetic mutation that affects mostly infants and young children. Tay-sachs is inherited in an autosomal recessive pattern (See illustration), meaning that both parents can carry one copy of the mutated gene in their DNA without symptoms, but if both copies are passed on to their child, their child will have the disease. The mutated gene in Tay-Sach’s is the the HEXA gene which provides instructions to make the enzyme beta-hexosaminidase, which is an enzyme in the lysosome that breaks down fatty substances. Without this gene functioning properly, a fatty substance called GM2 ganglioside builds up in nerve cells in the brain and spinal cord. Gangliosides are produced and broken down by the cell and thought to be important in neuroprotection, which means protecting the nerve cells from damage or degeneration. At regulated levels gangliosides are not damaging, but at unregulated levels, like in Tay-Sachs, it can cause the nerve cells to become swollen and not function properly. Because of this nerve cell breakdown, the affected individual slowly loses motor control and the ability to perform everyday functions. As this disease progresses, the affected individual loses the ability to function. Unfortunately, there is no cure for this disease.
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Viral Infection
Viral infections occur when a virus attaches to a cell and then enters it, releasing its DNA or RNA once inside the cell. The DNA or RNA the virus inserts provides instructions so the cell can produce more of that specific virus and forces the cell to produce it. The more the virus is replicated the more the virus spreads throughout the body. The most common viral infections are the flu, strep throat, and the common cold. Viral infections are spread in many different way including physical touch, such as shaking hands, or by coughing or sneezing.
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