The Ramazzini Institute
for Occupational and Environmental Health Research   

Who Are We?

     In the second, revised edition of Susan Oyama’s The Ontogeny of Information, just published by Duke University Press, Harvard geneticist Professor Richard C. Lewontin writes a preface for an important book. He does more. Lewontin provides a touchstone for judging the claims of both sides in the “nature versus nurture” controversy at the heart of regulatory, legislative and public policy disputes revolving around finding blame for disease. He provides a way of looking at the “gene” that establishes the common ground for groups as disparate as the advocates for doing something about genetic disorders and those interested in the natural, community and work environments.

     Part of the problem, Lewontin points out, is the casual way in which geneticists speak. “This is seen even in the naming of genes,” he notes. “Geneticists speak casually of the ‘gene for white eyes’, but of course, there is no such gene. There is a variety of genes whose reading by the cell is proximally involved in the production of eye pigment and its deposition in the eye cells.” He points out that genes are said to be “self-replicating”, engaged in “gene action”, “make” proteins and are “turned on “ or “off” by regulatory DNA. “But none of this is true… DNA is among the most inert and non-reactive of organic molecules, “ he writes.

     Lewontin does not deny the importance of genes: “ In the absence of DNA, there would be no development because there would be nothing for the cell machinery to read.” Nevertheless he forces us to rethink causation. Here he stresses the contribution of Oyama, whose view is much more than the idea of separable genes and environments interacting. The gene and the environment are not alternative causes, even though the differences between organisms can, in some special cases, be ascribed entirely to genetic or environmental differences. “For the most part,” he says, “differences between individuals are a consequence of both genetic and environmental differences.”

     “There are no ‘gene actions’ outside environments,” stresses Lewontin, “ and no ‘environmental actions’ can occur in the absence of genes. .. Organisms are the nexus of external circumstances and DNA molecules that make these physical circumstances into causes of development in the first place. They become causes only at their nexus, and they cannot exist as causes except in their simultaneous action.”

     The Lewontin-Oyama perspective should give us pause for thought every time we read claims that “all disease is genetic” or similar, if opposite claims by those on the other side of a dispute that has so little legitimacy.

---Sheldon W. Samuels