Dr. Tsubokura's Radiation Lecture Vol.112

Author: Masaharu Tsubokura PhD.

Editors: Akihiko Ozaki M.D.,PhD., Yuki Senoo

223. Genetic damage can be self-repaired

21.04.2019

There is persistent public concern that additional radiation exposure caused by the 2011 Fukushima Daiichi nuclear accident might cause adverse health effects in future generations. However, considering the current circumstances, the radiation exposure from the Fukushima Daiichi nuclear accident is unlikely to cause genetic health effects among members of the next generation.

Since the early 20th century, much research has been conducted on the transgenerational genetic risk of radiation exposure worldwide. In 1927, Dr. Hermann J. Muller, an American geneticist, discovered the transgenerational health risk of radiation exposure as observed in fruit flies. This discovery attracted international attention, and Dr. Muller received the Nobel Prize in Physiology and Medicine in 1946.

However, later studies’ results contradicted Dr. Muller’s findings. An investigation conducted in Hiroshima and Nagasaki reported no hereditary effects of radiation exposure among members of the second generation of atomic bomb survivors. Furthermore, another study demonstrated that the genetic risk of radiation exposure observed in fruit flies was not observed in mice.

Human bodies are capable of repairing the genetic damage caused by radiation exposure. In addition, it was later discovered that the sperm cells of fruit flies cannot repair the damage caused by radiation exposure. This difference in the ability to repair radiation damage determines whether genetic effects occur in offspring.

224. The risk of radiation-induced cancer is higher than the hereditary risk of cancer

28.04.2019

There is persistent public concern that additional radiation exposure caused by the 2011 Fukushima Daiichi nuclear accident might cause adverse health effects in future generations. However, considering the current circumstances, radiation exposure from the Fukushima Daiichi nuclear accident is unlikely to cause genetic health effects among members of the next generation.

In 1927, a study by Dr. Hermann J. Muller found that fruit flies that underwent radiation exposure passed the radiation’s genetic effects to their offspring. The following year, a study reported that genetic mutations caused by radiation exposure were observed in plants. A few years later, another study also demonstrated the transgenerational effects of ultraviolet light.

In this context, the transgenerational effects of radiation exposure became the center of public health concern because of the radioactive fallout deposited worldwide by the atomic bombings of Hiroshima and Nagasaki, as well as the repeated nuclear tests conducted following the Second World War.

However, when mice—whose bodies are much more similar to humans than those of files—were used as experimental subjects, the long-term damage caused by radiation exposure was much less severe. In addition, an investigation of the impact of the Hiroshima and Nagasaki atomic bombings revealed no significant transgenerational radiation effects among the second generation of atomic bomb survivors.

From this finding, the international Committee on Radiation has determined that the cancer risks radiation poses to humans is more extensive than its heredity risk.

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The Japanese version of the manuscript was originally published in Fukushima Minyu, a local newspaper in Fukushima prefecture, Japan, 21th and 28th April 2019 was reproduced for MRIC Global under the author's permission.