2 0 3 HETEROGENEITY IN TELOMERE LENGTH ON HUMAN CHROMOSOME

Telomere sequence perceived at the end of each chromosome serve as an effective biomarker of a cell’s replicative history. The average telomere length from blood and cheek cells of three persons of same age are found out by (terminal restriction fragment) TRF analysis. The concentration of isolated genomic DNA was determined and then double digested with restriction enzyme. By means of electrophoresis the length of telomere is calculated by comparing with DNA marker. Genetic variation in these telomeric region was also found out by DNA sequencing. The telomere from blood sample of third person showed a maximum length of more than10,000kb. Even though the blood sample and cheek cells from first and third person respectively showed same length, they differ in their genetic sequences. Various diseases like aging, cancer, anemia, Alzheimer, atherosclerosis, cardiovascular disease, hepatitis, chronic inflammatory bowel disease, and chronic HIV infection can be diagnosed by having a good knowledge on telomere length.

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