・In Japan, it is possible to perform human embryo research under regulations, but without sufficient explanation, the research would give cause for societal concern. 

・Issues related to genome editing medicine to prevent the inheritance of severe genetic diseases in offspring are presented.

Last year, we looked at the possibilities for human germline genome editing research and found problems with the related regulations. Now, after a detailed analysis of genome editing research in mammals, we see that gene modification of embryos, spermatogonial stem cells, and oocytes is being conducted using not just mice but also medium- to large-sized animals, and even though there are technical issues such as the introduction of modifications other than at the target sites, we estimate that the level of clinical application will be attained in the near future. We checked into the regulations on research accompanying the creation of human embryos, and found that such research is permitted under regulations in several countries including Japan. We also summarized issues regarding the appropriateness of germline gene editing research, considering topics such as preimplantation diagnosis as well as mitochondrial replacement through nuclear transfer between oocytes or embryos (regulations proposed in England regarding mitochondrial replacement were approved this year). As a result, we found that gene editing research aimed specifically at preventing the inheritance of severe genetic diseases in children could be appropriate. However, an understanding of the ethical status of embryos, and protection of the dignity of the unborn child, will be important issues for the future. For the present, as further improvements are expected in safe genome editing, we propose starting a wider discussion involving the general population.

Tetsuya ISHII, Professor, Office of Health and Safety, Hokkaido University

TEL: +81-11-706-2126

FAX: +81-11-706-2295

E-mail: tishii@general .hokudai.ac.jp