title: Telomere length in Chernobyl accident recovery workers in the late period after the disaster.
abstract: The outcome of the Chernobyl nuclear power plant (CNPP) accident was that a huge number of people were exposed to ionizing radiation. Previous studies of CNPP clean-up workers from Latvia revealed a high occurrence of age-associated degenerative diseases and cancer in young adults, as well as a high mortality as a result of cardiovascular disorders at age 45-54 years. DNA tandem repeats that cap chromosome ends, known as telomeres, are sensitive to oxidative damage and exposure to ionizing radiation. Telomeres are important in aging processes and carcinogenesis. The aim of this study was to investigate the long-term effect of protracted ionizing radiation exposure on telomere length in CNPP clean-up workers. Relative telomere length (RTL) was measured in peripheral blood leukocytes of 595 CNPP clean-up workers and 236 gender- and age-matched controls using real-time quantitative polymerase chain reaction (q-PCR). Close attention was paid to participation year and tasks performed during the worker's stay in Chernobyl, health status, and RTL differences between subgroups. Telomere shortening was not found in CNPP clean-up workers; on the contrary, their RTL was slightly greater than in controls (P = 0.001). Longer telomeres were found in people who worked during 1986, in those undertaking 'dirty' tasks (digging and deactivation), and in people with cancer. Shorter telomeres appeared frequently in those with cataract, osteoporosis, atherosclerosis, or coronary heart disease. We conclude that the longer telomeres revealed in people more heavily exposed to ionizing radiation probably indicate activation of telomerase as a chromosome healing mechanism following damage, and reflect defects in telomerase regulation that could potentiate carcinogenesis.
authors.affiliation: Institute of Occupational Safety and Environmental Health, Riga Stradins University, Dzirciema Street 16, Riga, LV-1007, Latvia Centre of Occupational and Radiological Medicine, Pauls Stradins Clinical University Hospital, Pilsonu Street 13, Riga, LV-1002, Latvia jelena_reste@yahoo.com.
authors.forename: Jelena
authors.initials: J
authors.lastname: Reste
authors.affiliation: Institute of Oncology, Riga Stradins University, Dzirciema Street 16, Riga, LV-1007, Latvia.
authors.forename: Gunda
authors.initials: G
authors.lastname: Zvigule
authors.affiliation: Institute of Occupational Safety and Environmental Health, Riga Stradins University, Dzirciema Street 16, Riga, LV-1007, Latvia Centre of Occupational and Radiological Medicine, Pauls Stradins Clinical University Hospital, Pilsonu Street 13, Riga, LV-1002, Latvia.
authors.forename: Tija
authors.initials: T
authors.lastname: Zvagule
authors.affiliation: Institute of Occupational Safety and Environmental Health, Riga Stradins University, Dzirciema Street 16, Riga, LV-1007, Latvia Centre of Occupational and Radiological Medicine, Pauls Stradins Clinical University Hospital, Pilsonu Street 13, Riga, LV-1002, Latvia.
authors.forename: Natalja
authors.initials: N
authors.lastname: Kurjane
authors.affiliation: Institute of Occupational Safety and Environmental Health, Riga Stradins University, Dzirciema Street 16, Riga, LV-1007, Latvia Centre of Occupational and Radiological Medicine, Pauls Stradins Clinical University Hospital, Pilsonu Street 13, Riga, LV-1002, Latvia.
authors.forename: Maija
authors.initials: M
authors.lastname: Eglite
authors.affiliation: Centre of Occupational and Radiological Medicine, Pauls Stradins Clinical University Hospital, Pilsonu Street 13, Riga, LV-1002, Latvia.
authors.forename: Natalija
authors.initials: N
authors.lastname: Gabruseva
authors.affiliation: Institute of Oncology, Riga Stradins University, Dzirciema Street 16, Riga, LV-1007, Latvia.
authors.forename: Dace
authors.initials: D
authors.lastname: Berzina
authors.affiliation: Institute of Oncology, Riga Stradins University, Dzirciema Street 16, Riga, LV-1007, Latvia.
authors.forename: Juris
authors.initials: J
authors.lastname: Plonis
authors.affiliation: Institute of Oncology, Riga Stradins University, Dzirciema Street 16, Riga, LV-1007, Latvia.
authors.forename: Edvins
authors.initials: E
authors.lastname: Miklasevics
mesh_terms: D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D047852:Chernobyl Nuclear Accident; D003430:Cross-Sectional Studies; D006801:Humans; D007962:Leukocytes / Q000528:radiation effects; D008297:Male; D008875:Middle Aged; D016273:Occupational Exposure; D016615:Telomere / Q000235:genetics / Q000528:radiation effects; D059505:Telomere Homeostasis / Q000235:genetics / Q000528:radiation effects*; D059506:Telomere Shortening / Q000235:genetics / Q000528:radiation effects; D013997:Time Factors
keywords: Chernobyl nuclear power plant accident; aging-associated diseases; cancer; clean-up worker; protracted radiation exposure; telomere length