biological basis of Huntington disease

The biological basis of HUNTINGTON'S DISEASE Huntington's disease is a genetic disease because it results from the alteration of a gene and is characterized by the possibility of transmission to the offspring of the affected person. Each cell in the body has chromosomes consisting of genes, which are small pieces of genetic material.  The gene responsible for Huntington's disease (IT15) is located on chromosome 4. Genes are made ​​of a substance called "deoxyribonucleic acid" or DNA . DNA contains the information the body needs to make proteins assume specific functions.  The coded information contained in DNA is represented by four letters: A (adenine), G (guanine), T (thymine ) and C (cytosine), which are chemicals.  These letters are combined into groups of three, called codons, which represent the amino acids (basic building blocks of protein, essential elements of the life of the cell). The shape of a protein is therefore determined by the amino acids that compose it, and their order. This unique form in the space control how the protein fits and interacts with other parts of the cell. Thus, a protein works successfully originates codons of the DNA. When a protein is modified, it has neither the size nor the desired shape and can not function properly in the nerve cell.  And it can not function properly, it prevents other proteins, whose work depended his, to function properly.  The end result is a snowball effect, the problems accumulate continuously and the nerve cell becomes increasingly damaged and die. * * * * * When the DNA code contains the letters CAG, it tells the cell to produce glutamine, an amino acid found in certain proteins, including, in the protein huntingtin. All human beings have in their nerve cells, the protein huntingtin , whose exact function has not yet been determined by scientists but clearly plays a critical role in the events that allows cells to function effectively. In people with Huntington's disease, there is an excessive number of glutamines in a segment of the protein in particular, due to too many copies of the corresponding codon (CAG-one who code "glutamine") in the DNA code.  huntingtin protein becomes toxic. Scientists seek to know why the huntingtin protein as amended (huntingtin protein) is harmful. One study suggests that over-abundance of glutamines in the huntingtin protein cause the formation of agglomerates rigid protein.  And like the other cell components are designed to work in a more flexible, they can no longer work in this size increased.  The end result is death anticipated the nerve cell (called apoptosis ). Another recent study suggests that the altered huntingtin protein "kidnaps" smaller proteins of the nerve cell, preventing them from doing their job.  Thus the huntingtin protein can damage the nerve cells directly.

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