Blank and of DNA, with its ribose-phosphate chains and associated cations in solution as the charge bearing and charge con-Goodman, 1997], ''Do electromagnetic fields interact ducting parts of the biopolymer assembly, has been exdirectly with DNA?'', was and remains open in our panded. The double helix is also capable of very high minds. As stated in Dr. Adair's communication, there electronic conduction through the stacked base pairs [Danare reasons for answering the question in the negative, dliker et al., 1997]. It is also possible to make a base flip but there are also reasons for considering a positive out of the double helix without major distortion of other reply. Our paper was not submitted to a physics journal, parts of the DNA [Klimasauskas et al., 1994], and large but was critically reviewed and published in Bioelecconformational changes in DNA can result from small tromagnetics, where the prefix in the title indicates that changes in charge density [Strauss and Maher, 1994]. This biology should be considered, perhaps even be primary.
new information raises the possibility that current flow This was our intention.
within the DNA may lead to significant interactions with The reasons for recognizing biological evidence the relatively weak magnetic fields, and thereby initiate are compelling. At various times, physical arguments the changes in DNA that stimulate transcription. have been advanced that effects on magnetic fields are Our knowledge of specialized biological recepnot possible below 100 mT, 10 mT, or even 5 mT. There tors shows that biological structures frequently have are, however, numerous reports of biological effects unusual properties. We encourage physicists to conbelow these field strengths. A recent (March 24 -27, sider the growing information about DNA and to ex-1997) NIEHS workshop on ''Theoretical Mechanisms plore the development of relevant physical models to and In Vitro Research on Magnetic Fields'' evaluated explain these properties. studies showing altered levels of mRNAs and proteins, increased enzyme activities, altered endocrine and hor-Martin Blank monal expression, and changes in signal transduction Reba Goodman pathways. Many of these effects were at field strengths Departments of Physiology and Pathology well below the levels set by arguments from physics, Columbia University and many of the experiments have been replicated.