%0 Journal Article
%T Premature chromosome condensation assay to study influence of high-level natural radiation on the initial DNA double strand break repair in human G0 lymphocytes.
%A Vivek Kumar PR
%A Karuppasamy CV
%A Ramachandran EN
%A Anil Kumar V
%A Jaikrishan G
%A Das B
%J Mutat Res Genet Toxicol Environ Mutagen
%V 849
%N 0
%D Jan 2020
%M 32087855
%F 3.189
%R 10.1016/j.mrgentox.2020.503141
%X The inherent capacity of individuals to efficiently repair ionizing radiation induced DNA double strand breaks (DSBs) may be inherited, however, it is influenced by several epigenetic and environmental factors. A pilot study tested whether chronic low dose natural radiation exposure influences the rejoining of initial DNA DSBs induced by a 2 Gy γ-irradiation in 22 individuals from high (>1.5 mGy/year) and normal (≤1.5 mGy/year) level natural radiation areas (H&NLNRA) of Kerala. Rejoining of DSBs (during 1 h at 37 °C, immediately after irradiation) was evaluated at the chromosome level in the presence and absence of wortmannin (a potent inhibitor of DSB repair in normal human cells) using a cell fusion-induced premature chromosome condensation (PCC) assay. The PCC assay quantitates DSBs in the form of excess chromosome fragments in human G0 lymphocytes without the requirement for cell division. A quantitative difference was observed in the early rejoining of DNA DSBs between individuals from HLNRA and NLNRA, with HLNRA individuals showing a higher (P = 0.05) mean initial repair ratio. The results indicate an influence of chronic low dose natural radiation on initial DNA DSB repair in inhabitants of HLNRA of the Kerala coast.