Tokyo

Survivors of Hiroshima: tracking their descendants will indicate genetic effects of nuclear war. Credit: AP

Children born to survivors of the 1945 atomic blasts in Japan are to be the subjects of a new study investigating the long-term effects of the atomic bomb. The research, which gets under way this month, will track the onset of diseases such as heart disease and diabetes, which are unlikely to show up until adulthood.

The work will be done by the Radiation Effects Research Foundation (RERF), a nonprofit private foundation funded jointly by the United States and Japan. RERF has laboratories in Hiroshima and Nagasaki — the two cities bombed with nuclear devices in 1945 by the United States.

To date, RERF has found no long-term genetic effects in the so-called F 1 population, the roughly 80,000 children born to survivors of the US attacks between 1946 and 1984. But this result has surprised some researchers, as radiation has shown powerful genetic effects in animal experiments.

One possible explanation could be the technical limitations of the studies themselves, says Seymour Abrahamson, a fruitfly geneticist from the University of Wisconsin-Madison who recently joined RERF as its research director. “We know a lot more now about genetic diseases,” he says.

The only systematic clinical study on F1 children was carried out between 1948 and 1953. Most of these were based on observations by doctors and midwives, who reported stillbirths and physically apparent abnormalities in children less than one year old.

Abrahamson says that there is still a possibility that radiation effects will show up as “late onset, multifactorial” genetic disorders not visible at infancy. “We have to close the circle,” he says.

In January, RERF will conduct a postal survey of 20,000 people in the F 1 population to find out how many will be willing to undergo a full-scale clinical analysis. Data on health records and physical examinations will then be collected. It will probablytake between four and six years for results from the analysis to appear, Abrahamson says.

But some of the study's potential subjects are opposed to the research because they fear that finding a genetic effect could lead to discrimination. Others, meanwhile, hope that a link between radiation and ill-health could justify their demands for benefits from the government. Only this year, Japanese courts awarded compensation from the government to plaintiffs who claimed that their illnesses were caused by the 1945 bombing. “This study is likely to influence such court decisions in the future,” Abrahamson says.

→ http://www.rerf.or.jp/eigo/experhp/rerfhome.htm