Telomeres<br />Telomeres main function is by preventing chromosomes<br />from losing base pair sequences at their ends.<br />They also stop chromosomes from fusing to each other.<br />Telomeres are the repeating sequences of DNA<br />Example-(TTAGGG).<br />In human blood cells, each time a cell divides, an <br />average person loses about 115 base pairs from the <br />ends of that cell's telomeres. The length of telomeres <br />is about 8,000 base pairs at birth. As people age they <br />can have as low as 1,500 in elderly people.<br />
How Are Telomeres Related To<br />Aging & Cancer<br />Aging- Geneticist Richard Cawthon did an experiment where he <br />divided people in to two groups, one group of people with long <br />telomeres and one group of people with short telomeres. He found <br />that the group with long telomeres lived longer and were healthier <br />than those with shorter telomeres. He concluded that telomeres play <br />a key role in aging and overall health. <br />Cancer-If a cell begins to become cancerous, it divides more often,<br />and its telomeres become very short. If its telomeres get too short, <br />the cell could die. Studies have found shortened telomeres in many <br />cancers, including pancreatic, bone, prostate, bladder, lung, kidney, <br />and head and neck.<br />
Telomerase<br />Telomerase (telomere terminal transferase) is an <br />enzyme made of protein and RNA that help <br />chromosomes by adding TTAGGG sequences to the <br />end of existing chromosomes to keep telomeres. <br />Telomerase is found in fetal tissues, adult germ cells and <br />also tumor cells.<br />In young cells, telomerase keeps telomeres from wearing <br />down too much. But as cells divide repeatedly, there is <br />not enough telomerase, so the telomeres grow shorter <br />and the cells age.<br />
How Is Telomerase Related Aging and Cancer<br />Aging-As cells divide repeatedly(50-70 times in their lifetime), <br />there is not enough telomerase for all the divisions of the cell. The <br />telomeres grow shorter and the cells age. Scientists have used <br />telomerase to stop cells from aging. <br />Cancer- The whole point of telomerase is to preserve telomeres by keep <br />adding telomeres to the chromosome. And Telomerase has been <br />increased in cancer cells, which means cancer cells are theoretically <br />immortal. Scientists have used telomerase to divide cells far beyond the <br />normal limit and the cells did not become cancerous. <br />
Technology Behind <br />Telomeres And Telomerase<br />If telomerase makes cancer cells immortal, it <br />could theoretically prevent normal cells from <br />aging. We (humans) all have the gene to make <br />telomerase, but it’s switched off.<br />Scientists are exploring the possibility of<br />inserting a gene for telomerase into aging cells or <br />developing a drug to turn on the gene for <br />telomerase. There is still research going on how to <br />make the cancer cells stop getting telomerase. <br />
In Theory<br />Measuring telomerase may be a new way to detect <br />cancer. If scientists can learn how to stop <br />telomerase, they might be able to fight cancer by <br />making cancer cells age and die.<br />But there are risks. Blocking telomerase could impair <br />fertility, stop healing, and production of blood cells and <br />immune system cells. <br />If telomerase could be used routinely to immortalize <br />human cells, it would be theoretically possible to mass <br />produce any human cell for transplantation.<br />
Works Cited<br />Genetic Science Learning Center. "Are Telomeres the Key toAging and Cancer?." Learn.Genetics<br />5 February 2011<http://learn.genetics.utah.edu/content/begin/traits/telomeres/> .<br />Aten, David. "What are telomeres and telomerase?." Shay/Wright Laboratory. N.p., September 6, 2007.<br />Web. 5 Feb 2011. <http://www4.utsouthwestern.edu/cellbio/shay-wright/index.html>. <br />"Graphic: Telomeres and Telomerase." Web. 5 Feb 2011.<br /><http://www.bing.com/images/search?q=telomeres&view=detail&id=CA081E65DF5545037D3A1A34<br />968CBE3E0F21677&first=1&FORM=IDFRIR>. <br />"Telomerase." Geron. N.p., n.d. Web. 5 Feb 2011.<br /><http://www.geron.com/technology/telomerase/telomerase.aspx>. <br />"Regulation of telomere length in normal and cancer cells by telomerase." Web. 5 Feb 2011.<br /><http://www.bing.com/images/search?q=telomermase&view=detail&id=5B39D66AE69E6D9E91BE578D843<br />781371DE3D58&first=1&FRM=IDFRIR>. <br />
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