Background
Before the project began a background literature review was done to understand the basis of the project, including any existing studies that overlap my research and studies that directly relate to my invertigation.
Muscular dystrophy (MD) is a genetic disorder that weakens the muscles that help the body move. People with MD have incorrect or missing information in their genes, which prevents them from making the proteins vital for healthy muscles. MD is genetic, so people are born with the problem — it is not contagious and you can't catch it from someone who has it. MD weakens muscles, so those with the disease can gradually lose the ability to do most physical activities e.g. walking. Someone with MD may start having muscle problems from birth or later in life. There are over 30 types of MD with various symptoms but this particular piece will explore Duchenne Muscular Dystrophy (DMD).
Duchenne muscular dystrophy is a neuromuscular condition. It is the most common type of MD Duchenne Muscular Dystrophy. (DMD) is an X-linked disorder which affects about 1 in 3,500 males. Females are usually carriers of the defective gene that causes the disorder. Under Mendelian inheritance, when a mother carries the defective gene, her female child will have 50% chance of being a carrier and her male child will have 50% chance of having the disease and showing the symptoms. Although the disease is present from conception, symptoms usually develop before the child is 5 or 6 years old. (NHS UK).
DMD is the result of a mutation in the dystrophin gene, which is located on X chromosome (gene locus Xp21.2). That explains why male offsprings are particularly susceptible. DMD produces no functional dystrophin protein . The protein, ca...
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...electroporation, microbubbles and ultrasound.
Challenges facing gene therapy
The common problem for gene therapy is the concern about immune rejection by the target cell. Foreign proteins and DNAs are introduced into the body which will often illict an immune response. Even for the use of plasmids, though it does not contain any protein as they are “naked” DNA, the product will still be a protein which in any case may induce an immune response from the body.
Another hurdle is that the expression of the desired genetic product is often localized to the tissues in which the vectors are introduced. Thus muscle-targeting vectors need to be developed to allow systemic treatment of DMD. Finally, the use of viral vectors to introduce genetic material may carry a risk of insertional mutagenesis as fraction of the viral vector may be integrated into the host genome.
DMD also known as muscular dystrophy is muscular disease that occurs on young boys around age four to six. Muscular dystrophy is genetically transmitted disease carried from parent to offspring. This disease progressively damages or disturbs skeletal and cardiac muscle functions starting on the lower limbs. Obviously by damaging the muscle, the lower limbs and other muscles affected become very weak. This is ultimately caused by the lack dystrophin, a protein the body produces.
Duchenne Muscular Dystrophy, also known as DMD, is the most common form of muscular dystrophy. Muscular dystrophy is a condition that is inherited, and it is when muscles slowly become more and more weak and wasted. Duchenne muscular dystrophy is a form of muscular dystrophy that is very rapid and is most commonly found in boys. In muscle, there is a protein named dystrophin. Dystrophin is encoded by the DMD gene. When boys have Duchenne muscular dystrophy, they do not produce enough dystrophin in their muscles. This causes weakness in their muscles. Parents can tell if their child has duchenne muscular dystrophy by looking for various symptoms.
Sex-linked disorders only affect males and are passed down through female carriers. A boy inherits the disorder when he receives an X chromosome with a mutated dystrophin gene (the genetic cause) from his mother. The dystrophin gene is the largest gene found in nature and was identified through a positional cloning approach. It's a highly complex gene, a large rod-like cytoskeletal protein which is found at the inner surface of muscle fibers. www.ncbi.nlm.nih.gov - http://www.ncbi.nlm.nih.gov/.
Physiological Basis of disease: DMD is the commonest and most serious form of the dystrophies. The gene responsible for dystrophin which, when absent, causes DMD. Amount of dystrophin correlates with the severity of the disease (i.e., the less dystrophin present, the more severe the phenotype). Since the gene is on the X chromosome, it primarily affects males, and females who are carriers have milder symptoms ( www.nlm.nih.gov/medlineplus/ency/article/000705.htm).
The X-linked form of Emery-Dreifuss muscular dystrophy is caused by the EMD gene that codes for the ubiquitous protein called Emerin. The EMD gene is found on chromosome Xq28. The gene responsible for the X-linked form was identified in 1994. It is located on chromosome Xq28. The STA gene is 2100 bp in length, consists in six exons and encodes 762 bp mRNA. Its 34 kD protein product of 254 amino acids has been designated 'emerin'. Emerin is a protein that is part of the laminar-association protein family. Th...
Spinal Muscular Atrophy affects about 8 out of every 100,000 live births and also causes death among more babies than any other genetic disease out there. About one in every forty people has this gene in them but may not have SMA so they are a genetic carrier. But in order for a child to have SMA, both parents have to carry the mutated gene and passed it to the child. Therefore this causes the child to have double copies of the abnormal gene. About 1 in 40 men and 1 in 80 women are carriers of the gene.
Muscular Dystrophy is a genetic disorder in which your muscles drastically weaken over time. Muscles are replaced with “connective tissue,” which is more of a fatty tissue than a muscular one. The connective tissue is the tissue that is commonly found in scars, and that same tissue is incapable of movement. Although Muscular Dystrophy affects muscles in general, other types affect certain groups of muscles, and happen at different periods throughout a lifetime. For example one of the most common types, Duchenne Muscular Dystrophy, targets muscles in the upper thigh and pelvis. The disease is displayed throughout early childhood, usually between ages four and seven. This genetic disorder occurs only in boys. People have difficulty sitting up or standing and lose their ability to walk in their early teens. Sadly most people die by the age of twenty. A second common type, Becker’s Muscular Dystrophy affects the same muscles as Duchenne, but first appears in teenage years. Most people with Becker’s only live into their forties (Fallon 1824-1825).
Duchenne Muscular Dystrophy, commonly referred to as DMD, is a life threatening disease. There are many different forms of muscular dystrophy, Duchenne being one more serious. DMD begins to show at a young age. This particular form of muscular dystrophy is mostly found in males. Duchenne is carried by the mother on the X chromosome but often, the event of having this disease is just a “fluke.” Duchenne Muscular Dystrophy is a deadly and unfortunate disease but new research that is being done may be the cure many are looking for.
It is estimated that 1 out of every 5,600-7,700 boys ages 5-24 have Duchene or Becker muscular dystrophy. (“Data & Statistics,” 2012 April 6) Muscular dystrophy is a group of genetic diseases defined by muscle fibers that are unusually susceptible to damage. There are several different types of muscular dystrophy some of which shorten the affected person’s lifespan. (“Muscular dystrophy: Types and Causes of each form,” n.d.) There is a long history of the disorder but until recently there wasn’t much knowledge of the cause. (“Muscular Dystrophy: Hope through Research,” 16 April 2014) Symptoms are obvious and can be seen as soon as a child starts walking. (“Muscular Dystrophy,” 2012 January 19) Although muscular dystrophy mostly affects boys, girls can get it too. (“Muscular Dystrophy,” 2012 January 19) There is no cure for muscular dystrophy but there are several types of therapy and most types of muscular dystrophy are still fatal. (“Muscular Dystrophy: Hope through Research,” 16 April 2014)
To conclude, although gene therapy can cure a wide variety of diseases which cannot be cured by traditional medicine, and patients can get permanent cure without rejections, it can be high-risk and immoral. The negative effects of gene therapy lead to the shrink of the number of volunteers, and many trials have been forced to cease. The Gene therapy's potential to revolutionize medicine in the future is exciting, and hopes are high for its role in curing and preventing childhood diseases.
Duchenne muscular dystrophy, or DMD, was named after neurologist Guillaume Duchenne. During the late nineteenth century, Duchenne carried out experiments that included taking a biopsy of the living tissues from boys with DMD. Because of these experiments, Duchenne was the first to conclude that the disease was based in the muscles. Muscular dystrophy is a type of genetic disease that causes the progression of muscle atrophy and weakness. Duchenne muscular dystrophy is characterized as the rapid developing form of muscular dystrophy, and predominantly occurs in young males generally between the ages of three and five. Out of roughly three and half thousand births around the world, one baby will have this disease.
Spinal Muscular Atrophy is a disease that can destroy the “lower motor neurons in the nerve cells” (Spinal Muscular Atrophy, 2015). Spinal Muscular Atrophy affects the spinal cord that controls our everyday movement. These cells send out processes in the peripheral nerve to eventually make contact to our muscle, legs, arms, chest, breathing muscles. SMA is a very rare disease but it is the second most common recessive disease after cystic fibrosis. It is a very serious condition that has become a common genetic cause of death in infancy. This disease can influence our movement of our muscle and the ability to weaken our control movement, in this case the signal from our spine eventually will be lost. Refer to Figure 1 for a better understanding. If our motor neurons weakens or dies, it no longer sends the signal to our muscle movement, therefore cutting off any trace of signal between the muscle and the brain.
1 SanchezAndrea SanchezBiology 061Doctor HardinMonday, December 18, 2017Spinal Muscular AtrophySpinal Muscular Atrophy (SMA) it is a genetic disease that affects everything from the brain to your toes. It is a muscular diseases, therefore it affects all muscles in the body. The disease will affect motor cognitive ability things like clenching you fist or for newborns raising their head will be very limited due to this disease. This article outlines basic information on what the disease is. It explains the stages, the aspects of how it works and how there is treatment but no cure. (https://ojrd.biomedcentral.com/articles/10.1186/1750-1172-6-71). This article provides an insight how this disease began as well as how it is today. To specify it shows how the diseases how
For instance, the muscle degenerative disease sarcopenia or muscular dystrophy could be benefited from the inhabitation of this gene (Lee 2004). In the two studies conducted in regards to this topic when this gene was suppressed there was also evidence of a decrease in fibrosis, which leads to promising hopes for regeneration of some degenerative diseases (Lee 2004). However, there are still many doubts and uncertainties surrounding these experiments (Lee 2004).
Overall muscle weakness underlies the core features in classic DM1. Distal muscle weakness hampers dexterity of the hands, making grip myotonia a regular feature. However, myotonia also affects other muscles, such as the tongue or facial muscles. This causes difficulty with talking, chewing, and swallowing, and the ‘hatchet’ appearance on account of drooping eyelids and global facial weakness. Additionally, cardiac abnormalities arise – typically involving arrhythmias and conduction blocks, which contribute significantly to the morbidity and mortality of the disease. Central nervous system involvement covers intellectual deficits, Nocturnal apnoeic episodes and daytime sleepiness, , and specific patterns of psychological dysfunction. neuropsychological changes may be associated to alterations in biomarkers, such as tau protein abnormalities. These changes are often detected through neuroimaging and neuropathology. Furthermore, this multi-system disease may give rise to various gastrointestinal tract complications and endocrine abnormalities. Late-onset patients carry a lower number of repeat mutations and often experience symptoms of less