Race in the age of Genomic Medicine

The development of novel diagnostics, therapeutics and health services is increasingly predicated on the search for significant biological differences within and between populations. However, comparisons of these differences raise important scientific, social, ethical and policy questions. On the one hand, there is the potential to provide improved research, treatment and health services that are targeted for specific populations. However, by linking genetic information to socially defined categories, there is also the potential to reinforce crude biological notions of race and/or ethnicity and for the research to be misused in political, scientific or clinical contexts. If these latter issues are not addressed, scientific research in this area may be misconceived and lack public support.Race in the age of Genomic Medicine Symposiu

Research Ethics in Japan

アジア生命倫理リージョナルワークショップシンガポール会

Research Ethics in Japan

アジア生命倫理リージョナルワークショップマニラ会

Development of bioassay system for evaluation of materials for personal protective equipment (PPE) against toxic effects of ionizing radiations.

Health effects caused by ionizing radiations raise considerable concern among general public and radiation workers. To estimate ability of personal protective equipment (PPE) materials that reduce toxic effects of ionizing radiations, we developed an experimental bioassay system using Chinese Hamster V79 cells. The system developed here distinguished the biological effectiveness of X-ray that was significantly affected by elements composed of shielding materials. Survival of the cells exposed to sub-lethal dose of X-ray was enhanced more than 2 times when the X-ray was filtrated by a lead plate. Also filtration of the X-ray with a tungsten plate enhanced the cell survival more than three times. These results suggested the colony assay system developed here was useful for examination of the biological effectiveness of X-ray and the ability of PPE materials reducing the toxic effects caused by ionizing radiations

Identification of mouse mutant cells exhibiting the plastic mutant phenotype

To investigate the initial processes involved in radiation carcinogenesis, we isolated and examined mouse mutant cells exhibiting phenotype plasticity. Approximately 10% of 6-thioguanine resistant (6TGR) cells derived from the irradiated cell population exhibited phenotype plasticity and reverted to wild type HAT resistance (HATR). Similar mutant cells were also identified in an un-irradiated wild type cell population, but at a lower frequency. Ionizing irradiation enhanced the frequency of the plastic mutation approximately 24 times in our experiment. Treatment with 5-aza-cytidine did not affect phenotype plasticity. Detailed molecular analysis of the promoter region of the hypoxanthine phosphoribosyl transferase (Hprt) gene revealed that most cytidine residues were not methylated, even in 6TGR mutant cells, in which Hprt activity must be down-regulated. These results suggested that DNA methylation was not involved in mutant phenotype plasticity. We have identified a new type of genomic instability induced by ionizing radiation. Plasticity in gene regulation may play an important role in radiation carcinogenesis, which is a multiple-stages process.欧州エピジェネティクス会