Fragmentation of purified mammalian DNA molecules by ultrasound below human therapeutic doses.

Because of the increasing medical use of ultrasound, especially in obstetrical diagnosis, it has become important to check its genetic harmlessness. Purified calf thymus DNA in solution was exposed to both therapeutic and obstetrical diagnostic doses of ultrasound. Intensities lower than those used in therapy have a drastic effect on purified DNA in solution, although intensities used in obstetrical diagnosis caused no visible effect.