Essay on LHON: Mitochondrial Mutations and More

mutation is phenylalanine 508 known as delta F508. Delta F508 is a deletion of 3 nucleotides

An analysis of fifty-seven patients with GLUT1 deficiency syndrome was conducted by Leen and associates and seventeen different missense mutations of SLC2A1 were discovered. Of the seventeen mutations, a single nucleotide of adenine in the third helix domain of the SLC2A1 gene was substituted with a guanine. This missense mutation found on the 286th base pair caused the codon to generate the amino acid valine rather than methionine as seen on figure 2. This single missense mutation caused the classic phenotype expression of epilepsy in patient three, an 8-year-old female child. Two other patients in the study had a mutation in the third helix in the transmembrane portion of the protein, however their SLC2A1 gene contained a deletion rather than a missense

Once a upon time, there was a lonely mitochondria named Sophia Mitochondria. Sophia Mitochondria had been alone for a while and she does not know where her parents are. She want to find her parents so she decided to talk someone to help her which is her childhood best friend, David Chloroplast. However, before she called him, she did her normal routine. She took nutrients from one of their cells, breaks it down and turn it into energy. This routine is also known as cellular respiration. After that, she call her David Chloroplast and thirty minutes later, David Chloroplast was in front of her house. David Chloroplast and Sophia Mitochondria came to Bacteria Garden which Sophia Mitochondria’s parents favorite place to go every weekend. When they

Mitochondrial cytopathy is a genetic heritable disorder [5]. It occurs as a result of DNA mutation in the gem-line cells that can be transmitted to the second generation. This type of genetic disorder is often caused by mutations in the mitochondrial DMA versus the nucleic DNA. The mitochondria DNA is 20-30 times more susceptible to acquire mutations secondary to absence of DNA repair mechanisms in the mitochondria, giving rise to frequent point mutations or deletions in the mtDNA during cell division[1]. Such mutations are inherited exclusively from the maternal mitochondria. The paternal mitochondria do not contribute to the fetal mitochondria [6]. When some of the mitochondria in the ovum have mutations in their DNA, some of those defected mitochondria will go to daughter cells upon division. If the cells receiving the defected mtDNA contribute to forming tissues that are actively dividing after birth, they will be eliminated by the natural selection process after successive cell divisions. In contrast, if the cells inheriting the defected mitochondria developed into organs or tissues of limited dividing ability, this will result in problems related to energy metabolism in that organ [6]. Due to the random nature of the process, defected mitochondria may end up randomly in different types of tissue and at different concentration. This explains the variations in the manifestation, progression, prognosis and severity of the disorder.

What it is: Mitochondria are a part of eukaryotic cells and it takes in nutrients from the body and breaks it down and then it eventually turns it into energy.

There appear to be two categories of the disease - the sporadic form which does not seem to be inherited and the non-sporadic or the familial form. For a long time the wide spread hypothesis had been that the causes were almost exclusively due to environmental factors, even though in many cases the exact environmental factor has not been pinpointed. However, in 1996 there was a breakthrough discovery which suggested that a genetic alteration is capable of causing

It is a mitochondrial disorder inherited only from mothers because mitochondria are passed on to the developing embryo from egg cells (“Genetics Home Reference,”2013). Mitochondria are important structures inside the cells to generate ATP, a form of energy that can be used in our body. Since our eyes require large amounts of energy, any dysfunction of the mitochondria can have a dramatic effect in vision. The majority of patients diagnosed with LHON have genetic mutations in mitochondrial DNA (mtDNA). Approximately 90% of patients with LHON have one of three mtDNA mutations: m.11778G>A (the most common), m.3460G>A, or m.14484T>C (“Leber Hereditary Optic Neuropathy,” n.d., Causes section, para. 3). These mutated genes disrupt the proteins in the mitochondrial enzyme complex that help convert oxygen, fats, and simple sugars to energy which cause optic nerve cell damage (“Genetics Home Reference,”2013). It is important to note that even though an individual may be a carrier of one the gene mutations, does not mean they will develop the disease. Scientists have been unable to find out why it affects more males than

The mitochondria is commonly know as the “powerhouse” of the cell. It is a small structure in the cell that are made up of two membranes. Cellular respiration is the job of the mitochondria. Which means it takes in nutrients from the cell, breaks it down and turns it into energy. Then the energy is used by the cell for other functions. (“Gale Encyclopedia...”,2010)

The shape of the mitochondria perfectly allows it to produce at their best. They are made of two membranes. The membrane on the inside folds over many times and creates cristae, a layered structure. The membrane on the outside acts like skin, and covers the organelle. Inside the mitochondria, there is a contained liquid called matrix. In the matrix we can find ribosomes and floating DNA. We can also find here granules, which are structures which may control concentrations of ions. The surface area inside the organelle increases due to the folding of the inner membrane. Many of the chemical reactions that occur in the mitochondria take place in the inner membrane, so this increased surface area gives more space for the chemical reactions to occur. It´s like this, you can get more work done if you have more space to do the work. We can observe similar strategies involving surface area in the microvilli in our intestines.

Each cell contains hundreds to thousands of mitochondria (1), which are located in the fluid that surrounds the nucleus called cytoplasm. Mitochondria are organelles within cells that convert the energy from food into a form that cells can use. Mitochondria produce energy through a process called oxidative phosphorylation which is the final stage of cellular respiration. During oxidative phosphorylation, an electron transport chain works in conjunction with chemiosmosis to create energy molecules named adenosine triphosphate (ATP) using oxygen and simple sugars. In the electron transport chain, an electrochemical gradient is formed by the chemical gradient from the inside to the outside of a mitochondrion counteracting with the electrical gradient from the outside to the inside of the mitochondrion. During chemiosmosis, the energy stored in the gradient is used to make ATP.

Nuclear DNA mutations disrupt the respiratory chain by having a lack of one of the four complexes, more specifically, complex I deficiency is the most common and reported cause of nuclear DNA LS (JNNP). There is no exact or precise percentage of how often LS affects the population in either the United States or in the world since LS symptoms are often confused with other symptoms such as the baby boy’s who Leigh examined (UMDF). It is predicted that at least one in 40,000 infants are affected with LS though this also includes those who display LS symptoms

Mitochondrial disease is the malfunctioning of the mitochondria organelle located in every cell of the human body except the red blood cells. These organelles are responsible for the synthesis of 90% of the ATP energy required for a normal bodily function. Consequently if a patient is diagnosed with mtDNA disease, their individual cells will generate less energy than required resulting

A lot has to be learned about SMS, however, molecular analysis of the RAI1 gene, could be promising in the development of SMS Clinical Prediction Rules by using mutation prediction programs such as POLYPHEN, PANTHER, and PMUT. In a research conducted by Vilboux et al. (2011) two SMS clinical features demonstrated noticeable relationship to the RAI1 mRNA levels: ocular anomalies (Mann -Whitney Z= - 2.35; p=0.0188 and object insertion (Mann -Whitney Z = - 2.21; p=0.03.)

The role of DNA in cells is to store genetic information for extended periods of time. DNA are long strands that contain genetic code, or instructions, for the development and functions of living things. DNA tells cells what to do and how to function, they are found in the nucleus of a cell. The role of mitochondria in cells is to produce and supply the cell with energy, so it can complete its function. They can be found floating around in the cytoplasm of the cell. Mitochondria are able to duplicate or reproduce themselves without interfering with the replication of the cell and vise versa. The value of mitochondrial DNA (mtDNA) is to supply cells with energy by absorbing the sugars that were broken down from food. Mitochondrial DNA contains

Patients with this disorder express symptoms such as seizures, recurrent headaches, deafness, and vomiting, but in extreme cases can cause anorexia (due to excessive vomiting), diabetes, and damage to motor skills, vision, and sharpness of mind (Chinnery and Hudson 145; Choi et al 354). MELAS is one of the more common mtDNA diseases caused by mutations, resulting in an abundance of studies concerning patients with MELAS. The mutation that causes MELAS is usually heteroplasmic – it can only affect a certain proportion of mitochondria in a cell – but, in rare cases, it can be homoplasmic, as Choi et al discovered in their