Radiation damage passed through generations
NEW YORK (Reuters Health) - When radiation damages the DNA of mice, the damage is not limited to the animal exposed to the radiation, researchers in the UK report. The results of a new study show that this radiation-induced damage to DNA is passed on not only to the mouse's offspring, but to the next generation of mice as well. Download PDF Article
Elevated mutation rates in the germ line of first- and second-generation offspring of irradiated male mice.
Barber R , Plumb MA , Boulton E , Roux I , Dubrova YE
Department of Genetics, University of Leicester, Leicester LE1 7RH, United Kingdom.
Mutation rates at two expanded simple tandem repeat loci were studied in the germ line of first- and second-generation offspring of inbred male CBA/H, C57BL/6, and BALB/c mice exposed to either high linear energy transfer fission neutrons or low linear energy transfer x-rays. Paternal CBA/H exposure to either x-rays or fission neutrons resulted in increased mutation rates in the germ line of two subsequent generations. Comparable transgenerational effects were observed also in neutron-irradiated C57BL/6 and x-irradiated BALB/c mice. The levels of spontaneous mutation rates and radiation-induced transgenerational instability varied between strains (BALB/c>CBA/H>C57BL/6). Pre- and postmeiotic paternal exposure resulted in similar increases in mutation rate in the germ line of both generations of CBA/H mice, which together with our previous results suggests that radiation-induced expanded simple tandem repeat instability is manifested in diploid cells after fertilization. The remarkable finding that radiation-induced germ-line instability persists for at least two generations raises important issues of risk evaluation in humans. Download PDF Article
Recent Results: Radiation Effects on the Genetics of Sperm
Ionizing radiation damages DNA, and thus causes mutations in the genetic material. It has been known for a long time that embryos in utero are particularly sensitive to radiation damage, and restrictions are placed on the exposure of pregnant women to Xrays. In general the effect of radiation has been the cause of greater concern for women. Download PDF Article
X-ray Permitted Dose and its Relevance to Equine Semen Transport: Shielded Equitainer
Radiation has especially damaging effects on the cell cycle, and cells that are constantly reproducing (such as the gut) are especially vulnerable. This particularly includes embryonic cells. Permitted dose limits to pregnant women are therefore lower than for the normal population. The Equitainer shielding attenuates the X-ray dose below the permitted limit for pregnant women, and may be expected to be safe for equine semen. Download PDF Article