Edward J. Steele - Meta-Lamarckism and Research Legacy

Meta-Lamarckism and Research Legacy

Soma to germ-line feedback In the 1970s molecular immunologist Ted Steele and colleagues, proposed a neo-Lamarckian mechanism to try to explain why homologous DNA sequences from the VDJ gene regions of parent mice were found in their germ cells and seemed to persist in the offspring for a few generations. The mechanism involved the somatic selection and clonal amplification of newly acquired antibody gene sequences that were generated via somatic hyper-mutation in B-cells. The mRNA products of these somatically novel genes were captured by retroviruses endogenous to the B-cells and were then transported through the blood stream where they could breach the soma-germ barrier and retrofect (reverse transcribe) the newly acquired genes into the cells of the germ line. Although Steele was advocating this theory for the better part of two decades, little more than indirect evidence was ever acquired to support it. An interesting attribute of this idea is that it strongly resembles Darwin's own theory of pangenesis, except in the soma to germ line feedback theory, pangenes are replaced with realistic retroviruses.

In July 2006, Dr Corrado Spadafora published a paper providing evidence that male sex cells or sperm could indeed receive foreign genetic material - information from body cells being written back into the germline DNA. Spadafora presented evidence that a green fluorescent protein, a genetic tag attached to the sperm of a father subsequently showed up in the tissue or body cells of his progeny. He announced that there is in all mature spermatozoa, an efficient machinery to receive information from external DNA molecules and that this behavior is widespread. It has been observed in sperm from more than 30 species, from sea urchins to honey bees to humans. In about a quarter of cases the foreign genes have appeared in the next generation. Spadafora announced in his paper that the genetic transfer mechanism he had discovered involves the generation and 'non-Mendelian' spread of new genetic information beyond that supposedly locked up in the chromosomes.

Simultaneously, Patrick Fogarty was one of a number of scientists working with animals to develop new genetic transfer technologies for drug target discovery. In his experiments, transgenic animals that have ‘knock-in’ genes or ‘knockout’ genes are used to provide useful animal models for the development of gene therapies. In the process of conducting the early trials, scientists are finding that the genome of animals can integrate new genes, or have selected genes deleted, and that the progeny of new transgenic animals inherit the new genetic alterations.Fogarty, has developed two new delivery vectors that can be used to incorporate a new gene into the genome, or to replace a similar gene with a new one. In the laboratory he uses a mechanism to envelope foreign DNA which is then injected into the tails of mice. Each animal is directly injected with a mix containing the new gene and a vector designed to assist the integration of the new gene into the animal’s genetic makeup. In his experiments, Fogarty and his colleagues injected the vectors with the new DNA cargo into mice, and achieved effective gene transformations to create the transgenic effects they aimed for. He showed that over time, the new DNA became integrated into almost all somatic cells tested. There also appeared to be no side effects using this technique. What is most remarkable about this work, is that the progeny of the StealthGeneTM and the TGD transgenic animals were also transgenic. The new genetic material had not only entered the somatic cells. It had also altered the genome of the animals injected. Using only the male line, the new genetic information was inherited by twenty five to eighty percent of the progeny of the transgenic animals, depending on the test variables used. The new genome was stable for the four generations tested, and there appeared to be no strain or sex dependencies.

Science philosopher Ross Honeywill highlighted Steele's work by proposing that in finding the mechanism for Lamarckian evolution Steele had simultaneously combined the best of Darwin and Lamarck. He proposed a modern, well-supported Lamarckian theory could be devised, consistent with well-documented parts of modern molecular genetics, able to be articulated with a surviving core of Darwinian natural selection: a kind of Meta-Lamarckism. "Steele identified RNA as the critical transcription vehicle because unlike DNA, it was the medium that was out there in contact with what was going on in the body. It was the obedient servant that knew the secret language, the secret handshake. What a breakthrough it was to discover from Lamarck via Steele that RNA could take vital changes back to the DNA for generational improvements. But imagine what it means if the RNA is capable of carrying its own information through generations; imagine the Meta-Lamarckian consequences and opportunities written all over these discoveries."