Before the project began a background literature review was done too 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, called dystrophin, is situated in muscle fibres and is part of the dystrophin-glycoprotein-complex (DGC). The DGC provides a structural link between the actin cytoskeleton and the extracellular matrix, thus stabilising the sarcolemma during cycles of muscle contraction and relaxation. However, the precise mechanism by which dystrophin deficiency causes the destruction of muscle fibres is still unknown.
DMD is characterized by progressive loss of muscle function starting from the lower limbs. There is a gradual weakness of muscles in the legs and pelvis associated with muscle wasting. Because of this weakness, the child is able to walk only at a much later stage. General complaints in most boys with DMD are an abnormal manner with toe walking, this happens as the tendons around the heels tightens and develop a forward curvature of his spine – a “lordosis”. Physical examination may show shortened ankle tendons and tendon reflexes that are still present. ‘There is compensatory lumbar hyperlordosis, which disappears when the child is sitting. The calf muscles are large and feel quite firm or even rubbery due to replacement of muscle fibres by fibrofatty tissue’ a condition known as pseudohypertrophy. (Mohamed K, Appleton...