Background: Racial variations in the Relative telomere length have been clearly described or frequently studied. The Relative telomere length has emerged as a biological aging marker; however, the difference in the telomere length is debatable between Sudanese and Chinese individuals. Objectives: The current study investigated the difference in the Relative telomere length between Sudanese and Chinese subjects. Methods: The blood samples of Sudanese and Chinese healthy people were randomly collected, and their deoxyribonucleic acid was obtained in this study. The Relative telomere length was measured by the quantitative polymerase chain reaction. The difference in the Relative telomere length was analyzed using the Mann-Whitney U test. The degree of distribution in the Relative telomere length was assessed by the two-sample Kolmogorov-Smirnov Z test. Results: According to the obtained results, the difference in the Relative telomere length between Sudanese and Chinese individuals was statistically significant (P<0. 05). The frequency of the Relative telomere length distributed in Chinese subjects was statistically higher than the frequency reported for the Sudanese subjects (P<0. 05). Conclusion: A great difference was observed in the Relative telomere length between Sudanese and Chinese populations indicating the variation between Sudanese and Chinese races.

Introduction: The telomeric DNA together with its associated proteins protects the chromosome ends from degradation or aberrant recombination. Telomerase and telomere are closely associated with development of cancers. In this study we aim to investigate the significance of telomerase activity (TA) and telomere length (TL) in patients with acute promyelocytic leukemia (APL).Methods: Peripheral blood samples were taken from 20 APL patients during the diagnosis and from 25 healthy normal individuals at different age ranges. Telomerase activity (TA) was assessed by TRAP- ELISA and - PAGE procedures. Genomic DNA isolated from patient mononuclear cells was digested with Rsa1 and Hinf1 restriction enzymes; electrophoresis was performed in 0.8% agarose gels, and telomere length (TL) was determined by southern analysis using a Chemiluminescence-based assay.Results: As oppose to the normal individuals, telomerase activity was detected in peripheral blood mononuclear cells of all APL patients (P<0.001). Marked differences were observed in the sizes of the telomere length in the normal blood cells and APL leukemic cells. The leukemic cells of 18 of 20 (90%) patients with APL showed a significant reduction in the length of telomeric DNA, ranging from 2.3 to 6.7 kbp (median 3.5 kbp), while the telomere length in healthy normal individuals was 9.1 to 14.8 kbp (median 11.6 kbp) (P<0.000). In healthy individuals, the average TL was found to vary with age, and the rate of telomere shortening was age dependent. Conclusions: telomere length shortening and Telomerase up-regulation are closely associated with acute promyelocytic leukemia; therefore, they may be used as potential markers for diagnostic, prognostic and for therapeutic intervention in APL patients.

Background & Aim: Squamous cell carcinoma is the most common cancer in oral cavity with aggressive behavior. Many researches are done about pathogenesis and detection methods for this cancer. The purpose this research is the evaluation of the length of telomere in oral squamous cell carcinoma (OSCC) and its probably diagnostic value.Materials & Methods: We used the sensitive PCR technique based on primer extension method to determine the telomere length. The procedure steps were 1) DNA isolation 2) PCR assay 3) Electrophoresis for assessment of the PCR products 4) AgN03 staining. At last length of the telomere was determined in comparison with 1Kb marker.Results: In 5 cases of OSCC the telomere length was less than 5Kb and in the other 5 samples it was between 5-5.5Kb, but in all normal tissue samples length of the telomere was more than 5.5Kb (9.4-10.6Kb). The findings showed a significant statistical difference between two groups (P<0.01). Also with the more severe dysplastic changes, higher telomere shortening was seen.Conclusion: telomere length is shortened is shortened in OSCC compare with normal tissue and can be a useful marker for diagnostic aims.