I would like to discuss the following paper
paper by Richard C. Strohman. While I believe Dr. Strohman is
nutty, he gives an interesting discussion in this paper. Briefly summarizing, he says there is a coming revolution in biological understanding of the cell and that genetic determinism does not adequately support the complexity of the genome. He gives epigenetic phenomenon as an example that may be of influence.
Dr. Strohman retired in 1991 and this paper was published in 1997 and is very out of date. Much of the paper is over the philosophy of science rather than of actual research and explanations conducted, but none the less, if you are able to skip the philosophical pseudoscience you may find it a great paper for an intro to epigenetic studies.
Definition & Examples
The author is speaking about
epigenetics. Epigenetics is the study of reversible, heritable changes in gene regulation that do not change the genotype. Epigenetics is a type of
non-Mendelian inheritance, which is defined as heritable traits that segregate differently than defined in
Mendel's laws.
I wrote about an example of an epigenetic phenomenon
here, but there are many examples in the wikipedia entry for epigenetics.
This is what brought me to this paper. I feel it brings up a good topic in biology.
quote:
If genes don't determine us then what does? The answers that "The environment determines....", or that "Genes together with environment determine complex behavior" are really no help in biology because with either of these we are still left with the cell or organism as a neutral space in which random events somehow work out adaptive responses to changing conditions. I shall try to show that our major trouble... is that we have no theory of the cell or organism which explains how either of these manages to constrain or collapse an enormously complex realm of possibility to a given adaptive reality.
Some of the evidence the author uses against genetic determinism is:
quote:
Humans and mice have the same number of expressed genes (exclusive of socalled junk DNA) and yet they are radically different creatures. Older findings have revealed the similarity (98%+) between human and chimpanzee DNA and yet these two organisms manage to construct very different results from their nearly identical genes..."sibling species" show us organisms that appear to be identical under the most stringent anatomical observation and yet are found to be entirely different when examined at the level of their genes and of their proteins. These organisms offer the reverse of the human-chimp problem since they extract from extremely different genomes identical phenotypic end points.
The authors main point in the paper is,
quote:
...we have wrongly extended the theory of the gene to another area altogether; we have been lulled into reasoning that if the gene theory works at one level ... from DNA to protein ... it must work at all higher levels as well [for example epigenetics].
The purpose of this discussion is to get other ideas on if you think this author is correct in the above and other statements he makes in the paper. In my opinion, which I
alluded to earlier, I think he is wrong which I will try to show in the future. What do you think the impact epigenetics will have on genetic determinism and evolution?
Edited by mobioevo, : spelling
Edited by mobioevo, : definition
Edited by mobioevo, : added quotes and some more questions.
Edited by mobioevo, : No reason given.
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