Assessing the genotoxicity of chronic environmental irradiation by using mitochondrial DNA heteroplasmy in the bank vole (Clethrionomys glareolus) at chornobyl, ukraine

摘要

This study was designed to investigate whether or not chronic exposure to Chlornobyl radiation poses a molecular genetic risk to mammals by examining a relatively rapidly evolving genetic system, mitochondrial DNA(mtDNA). More mtDNA mutations (～19/100)and an increase in mtDNA heteroplasmy(～5/100) occurred in the cytochrome b gene of an exposed mother-embryo set when compared to a relatively unexposed mother-embryo set. However, this increase was not statistically significant(p > 0.05). Our results, in conjunction with previous molecular genetic research on small mammals from Chornobyl, suggest that chronic exposure to environmental ionizing radiation does not increase the number of nucleotide substitutions, as predicted by studies using acute or subacute exposures.