Other factors could explain the new

Other factors could explain the new Science findings, cautions Timothy Bestor, professor of genetics and development at Columbia University. For one, he suggests that the researchers choice of mouse strain could have influenced the study results. Radford and colleagues did not study inbred mice because those mice had more trouble surviving the restrictive diet needed for the experiment. (Inbred mice are often studied because they are genetically homogenous across generations.) Instead, Radford studied more genetically diverse mice that could better survive the poor nutrition regime. In turn, the health issues seen in the second generation of mice (which were born free of the sperm DNA changes seen in the first generation of the mice) could be somehow genetically inherent to this mouse model, he suggests. The study authors, however, say they built in checks against that possibility, such as comparing the mice with control mice of the same breed.