Global gene expression analysis in PBMCs of individuals from normal and high level natural radiation areas of Kerala Coast, India. Homo sapiens

Gene expression changes in human populations exposed to chronic low level radiation have important implications. There are few areas around the world where human population is exposed to elevated levels of natural background radiation. The high level natural radiation areas (HLNRAs) of Kerala coast in south west India is unique for its wide variation in the background radiation dose ( 1.5mGy/year are considered as HLNRA. We used microarray analysis to find out global changes in gene expression in peripheral blood mononuclear cells (PBMCs) of individuals belonging to different HLNRA groups as compared to individuals from normal level natural radiation areas (NLNRA). Overall design: Blood samples were collected from individuals of four different background dose groups (Normal level natural radiation areas (Group I, ≤1.5mGy/year, N=9) and three dose groups of high level natural radiation areas (Group II, 1.51-5.0mGy/year, N=9; Group III, 5.01-15.0mGy/year, N=11; and Group IV, >15.0mGy/year, N=7)). Peripheral blood mono-nuclear cells were isolated from each blood sample and used for RNA extraction and hybridization to Affymetrix Chip.