低線量放射線がゲノムDNAメチル化へ及ぼす効果

Long-term effect of low-dose ionizing radiation on various cellular function suggests possible involvement of epigenetic events such as controlling methylation status of genomic DNA. We evaluated change of methylation level at any particular genomic DNA regions by two experimental methods. In one experiment, genomic DNAs from human cells exposed with no, 0.1 or 1 Gy gamma ray were fragmented and mixed with MBD2 protein which specifically binds methylated DNA. Recovered DNAs from the fraction of MBD2-DNA complex were subjected to massive sequencing with Illumina Genome Analyzer IIx instrument and obtained sequence tags were mapped to hg 19 reference genome sequence. On the other experiment, the genomic DNAs were digested with a couple of methylation-sensitive and -insensitive restriction endonucleases, and performed semi-quantitative AFLP analysis to measure methylation difference in the endonuclease recognition sites among the three samples. Data processing and integration of both experiments are now in progress.第１回国際シンポジウム ゲノム障害から見た非がん性疾患研