Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Sperm and eggs fall foul of fallout

08.02.2002


470 nuclear weapons were detonated in Kazakhstan between 1949 and 1989
© SPL


Nuclear tests up gene mutation risk.

People in the remote former Soviet republic of Kazakhstan who were exposed to fallout from nuclear-weapon tests have more genetic mutations in their eggs and sperm than normal, researchers have found1. Their children could inherit health defects caused by such mutations.

The Soviet Union detonated 470 nuclear weapons at the Semipalatinsk nuclear-testing site between 1949 and 1989, many above ground. The blasts showered radioactive dust over a 100-kilometre area. Inhabitants received up to one-fifth of a lethal radiation dose.



This has reputedly caused cancer and other health problems amongst the area’s sparse population. But medical evidence has been meagre.

Scientists do not know whether this type of radiation exposure causes genetic damage in humans, and if so, whether the damage is passed on to children. The three generations of affected individuals now living in Kazakhstan enabled Yuri Dubrova of the University of Leicester, UK, and his team to start estimating the harm that has been caused.

The researchers found double the normal rate of genetic changes in people’s sperm and eggs. These cells form future offspring, so the mutations are likely to be hereditary.

"[Until recently] no one had been able to measure the genetic effects of exposure," says Dudley Goodhead, who directs the MRC Radiation and Genome Stability Unit in Harwell, UK. "[The Kazakhstan work] indicates that mutations can occur at an enormously high rate."

The researchers still do not know whether this genetic damage has caused health problems for the area’s children, or whether it will do so in the future, because mutations only rarely result in disease. "It wouldn’t be surprising," says Goodhead. But researchers agree that any effects of inherited mutations are likely to be small and difficult to detect against the normal incidence rates of cancer and disease.

People directly exposed to radiation by the atomic-bomb detonations in Japan during the Second World War and by nuclear accidents such as Chernobyl, suffer increased rates of cancer. But the common perception that exposed individuals bear children with deformities is not backed up by scientific study.

Measuring the legacy

Measuring the mutation rate caused by radiation has proved difficult, explains Goodhead. Any given gene will be affected rarely, so only a large population would reveal an accurate frequency - and no such human population exists.

Dubrova instead looked at DNA fingerprints, which show many short sections of DNA that spontaneously vary, or mutate, from generation to generation. In 1996, he showed that children born in Belarus after the Chernobyl disaster have a higher rate of such mutations2.

In the Semipalatinsk population, the team found that the more years people were exposed to the radiation, the greater their mutation rate.

Knowing how the rate varies with radiation dose could be used to screen populations for suspected exposure. "We’d love to know that," says David Rush, who studies the health effects of radiation at Tufts University in Boston.

Test ban

Alongside the Soviet Union, the United States carried out above-ground nuclear tests in the Nevada desert; both nations ceased testing with the Moscow treaty in 1963. The Semipalatinsk site was closed in 1989 as part of the campaign to establish a comprehensive test-ban treaty. This treaty has yet to be ratified.

The Kazakhstan population has since fought for financial and health compensation, and Dubrova hopes that his work might help their cause: "I would be delighted if that were the case," he says.

References

  1. Dubrova, Y.E. Nuclear weapons tests and human germline mutation rate. Science, 295, 1037, (2002).
  2. Dubrova, Y.E. et al. Human minisatellite mutation rate after the Chernobyl accident. Nature, 380, 683 - 686(1996).


HELEN PEARSON | © Nature News Service
Further information:
http://www.nature.com/nsu/020204/020204-10.html

More articles from Ecology, The Environment and Conservation:

nachricht Sinking groundwater levels threaten the vitality of riverine ecosystems
04.10.2019 | Albert-Ludwigs-Universität Freiburg im Breisgau

nachricht Protecting our climate, the environment and nature is the focus of a new communications project
04.10.2019 | IDEA TV

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Researchers watch quantum knots untie

After first reporting the existence of quantum knots, Aalto University & Amherst College researchers now report how the knots behave

A quantum gas can be tied into knots using magnetic fields. Our researchers were the first to produce these knots as part of a collaboration between Aalto...

Im Focus: A cavity leads to a strong interaction between light and matter

Researchers have succeeded in creating an efficient quantum-mechanical light-matter interface using a microscopic cavity. Within this cavity, a single photon is emitted and absorbed up to 10 times by an artificial atom. This opens up new prospects for quantum technology, report physicists at the University of Basel and Ruhr-University Bochum in the journal Nature.

Quantum physics describes photons as light particles. Achieving an interaction between a single photon and a single atom is a huge challenge due to the tiny...

Im Focus: Solving the mystery of quantum light in thin layers

A very special kind of light is emitted by tungsten diselenide layers. The reason for this has been unclear. Now an explanation has been found at TU Wien (Vienna)

It is an exotic phenomenon that nobody was able to explain for years: when energy is supplied to a thin layer of the material tungsten diselenide, it begins to...

Im Focus: An ultrafast glimpse of the photochemistry of the atmosphere

Researchers at Ludwig-Maximilians-Universitaet (LMU) in Munich have explored the initial consequences of the interaction of light with molecules on the surface of nanoscopic aerosols.

The nanocosmos is constantly in motion. All natural processes are ultimately determined by the interplay between radiation and matter. Light strikes particles...

Im Focus: Shaping nanoparticles for improved quantum information technology

Particles that are mere nanometers in size are at the forefront of scientific research today. They come in many different shapes: rods, spheres, cubes, vesicles, S-shaped worms and even donut-like rings. What makes them worthy of scientific study is that, being so tiny, they exhibit quantum mechanical properties not possible with larger objects.

Researchers at the Center for Nanoscale Materials (CNM), a U.S. Department of Energy (DOE) Office of Science User Facility located at DOE's Argonne National...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

International Symposium on Functional Materials for Electrolysis, Fuel Cells and Metal-Air Batteries

02.10.2019 | Event News

NEXUS 2020: Relationships Between Architecture and Mathematics

02.10.2019 | Event News

Optical Technologies: International Symposium „Future Optics“ in Hannover

19.09.2019 | Event News

 
Latest News

Composite metal foam outperforms aluminum for use in aircraft wings

23.10.2019 | Materials Sciences

Researchers watch quantum knots untie

23.10.2019 | Physics and Astronomy

A technology to transform 2D planes into 3D soft and flexible structures

23.10.2019 | Medical Engineering

VideoLinks
Science & Research
Overview of more VideoLinks >>>