CORRELATION OF TELOMERE LENGTH SHORTENING WITH SMOKING

Background: Telomeres are DNA sequences that can be found at the ends of chromosomes, and prevent them from being damaged, they show shortening every time with the cell division, and when it is below a minimal length, the cells interrupt their cell cycle. Cigarette smoke contains chemical compounds that contribute to the oxidative damage in cells. Method: subjects over 65 years old belonging to the INER ageing cohort, residents of Mexico City and asymptomatic respiratory patients were studied. A questionary was applied on demographic characteristics, smoking habits (active and passive), and the study groups were identified as active smoking (AS), passive smoking (PS) and non-exposed subjects (NE). Telomere length was measured in a serum sample using the quantitative method based on RT-PCR. Results: We compared clinical data and telomere length of 333 subjects, showing that non-exposed group are below the 10th percentile, with the smallest telomere size (NE 1.38 + 0.36 vs PS 1.50 + 0.40 and AS 1.41 +0.43). Conclusion: There is no evidence that telomere shortening have increased as a result of active or passive smoking. It is suggested that smoking is not the only one responsible for the presence of shorter telomeres.