On April 26th, 1986, the Chernobyl Nuclear Power Plant in what is now the Ukraine exploded. Individuals living in the nearby city of Pripyat, as well as those sent to put out the fire and respond to the radiation in the immediate vicinity, were exposed to high levels of ionizing radiation. This exposure resulted in increased rates of cancer and other diseases caused by ionizing radiation damaging their DNA.
One of the concerns for Chernobyl survivors was that the radiation may have caused DNA damage to their sperm and eggs. As a result, children born after the accident could potentially have increased numbers of mutations in their DNA and more health problems throughout life. This phenomenon is known to happen to the offspring of mice exposed to bursts of high intensity radiation. To see whether this happened, a team of researchers studied the DNA of 130 children born to parents who either lived or worked near the accident. They looked specifically at de novo mutations, or new mutations in a child’s DNA. These occur naturally, with about 50 to 100 such new mutations in each child’s DNA. The researchers found that this mutation rate was not increased in the children born in the years or decades after the explosion, suggesting that they do not have any more mutations than an average child might be expected to have.
One important caveat is that the children studied were principally conceived months or years after their parents were exposed to high levels of ionizing radiation. It’s possible that children conceived immediately afterwards may have different mutation levels then those born later. Moreover, it’s not clear why mice pass on damage from ionizing radiation to their offspring when none was found in the children of Chernobyl survivors. The researchers speculate that it has to do with the fact that mice in these experiments are typically exposed to one fast high intensity dose of radiation, whereas the parents in this study were exposed to lower doses over a longer period. The lack of increased de novo mutations in the children of Chernobyl survivors is an optimistic sign that the survivors of Chernobyl can expect their children’s health to be unaffected by the disaster.
Managing Correspondent: Emily Kerr
Popular Press Article: No excess mutations in the children of Chernobyl survivors, new study finds
Image Credit: Timm Suess: Chernobyl Reactor Gate