More On Polycythemia Vera
I blogged yesterday on a response from a former employee of the Agency for Toxic Substances to our report on the CDC agency. Former ATSDR official John Steward talked about the problems that can be associated with linking public health problems to environmental factors. He took issue specifically with our report’s suggestion that polycythemia vera clusters in eastern Penn. are linked to environmental causes.
I pointed out that polycythemia vera, a very rare form of blood cancer, is not a genetic disorder, as Steward suggested, even though it can result from a genetic mutation — in the JAK2 gene. According to the National Institute of Health, it is not passed from parent to child.
Geneticist Dante Picciano emailed me responding to yesterday’s post. He explained the scientific difference between an inherited genetic disorder and a genetic mutation:
Genetic disorders are transmitted from one generation to the next and are caused by mutations to the reproductive cells. Sickle cell anemia is a classic example of a genetic disorder. Polycythemia vera is not a genetic disorder. It is not transmitted from generation to generation. The disorder may have a genetic component in that a somatic cell (body cell) mutation, as opposed to a reproductive cell mutation, may be associated with the disease. It may be that environmental exposures cause or contribute to the somatic mutation.