Biology of Belief - Bruce Lipton

[Routaran]

Hello,
I've just started reading this book and I'm confused by the ideas he's putting forth as its going aginst what i have read from other sources. I'm keeping an open mind and reserving judgement till I've read the whole book.

In chapter 1, it seems to me that he's doing away with "walls" that separate species because of gene transfer between specieis and quotes Daniel Drell from Science (2001 294:1634) saying "we can no longer comfortably say what is a species anymore." I am aware that horizontal gene trasnfers were present at the very beginings of life according to evolution but he seems to be indicating that this is happening even now and frequently...

I have tried to find this article on the internet so i can read the quote within the context to see what exactly Drell was talking about but i can't seem to find it. I was hoping poeple here would be ablet o help me find or teach me how to search for references. I'm a novice as this sort of thing. I would greatly appreciate any assistance.

Thanks.


Edit: I decided i'd just add the paragraph in question that confused me.

Recent advacnes in genome science have revealed an additional mechanism of cooperation among species. Living organisms, it turns out, actually integrate their cellular communities by sharing their genes. It has been thought that genes are passed only to the progeny of an individual organism through reproduction. Now scientists realize that genes are shared not only among the individual members of a species but also among members of different species. The sharing of genetic information via gene transfer speeds up evolution since organisms can acquire "learned" experience sfrom other organisms. (Nitz, et al, 2004: Pennisi 2004; Boucher, et al, 2003; Dutta and Pan 2002; Gogarten 2003) Given this sharing of genes, organisms can no longer be seen as disconnected entities; there is no wall between species. Daniel Drell, manager of the Department of Energy's microbial genome program told Science(2001 294:1634) "we can no longer comfortably say what is a species anymore." (Pennisi 2001)

 

[madcat8000]

Well as for prokaryotes, they don't fit well into Carl Linnaeus's system. Bacteria, Archea, and Viruses "horse trade" genes constantly. However eukarotes do fit much more comfortably into species because gene transfer outside of sexual reproduction is extreemly rare. Is there a specific part of those ideas you have trouble with?

http://www.sciencedaily.com/releases/2007/03/070308220454.htm

 

[mishrashubham]

There are several thousands of complete viral genomes integrated into our own genomes. Although useless (and sometimes dangerous) to us, they have been put there by retroviruses long back in the genomes of our ancestors and they have been passed on to each successive generation. The AIDS virus is a kind of retrovirus and uses the enzyme called reverse transciptase to integrate its genome into ours. In fact they make up about 5-8 % of all our genes and that is a lot; considering that only 3% of our genome codes for something useful and the rest is just junk.

http://en.wikipedia.org/wiki/Retrovirus

 

[Routaran]

@mishrashubham: I'm not sure if Lipton is talking about retroviruses in these seciton of his book when he's talking about gene trasnfer, but thank you for the info nevertheless. he hasnt mentioned it at all. the only thing he's said is "gene transfer" between species.
@madcat: thank you for clearing that up for me. i was under the assumption that this did not happen frequently. I only have a grade 10 biology education (i'm a computer programmer) can you please tell me why prokaryotes are able to exchange genes constantly while eukarotes are not? references that i could read would be very much appreciated

also, in the next paragraph of the book, Lipton states that engineering plants is a very bad idea and brings up an example of genetically engineered agricultural crops transfering genes to surrounding native species which gave rise to superweeds.

this still doesn't make sense to me. i thought super weeds came from our overuse of weedicides/pesticides etc. and the weeds/pests developing resistance. Also, I was under the impression that all plants fell under the category of eukarotes. why would he consider this a serious problem if transfer outside of sexual reproduction was rare. I'm assuming species like tomato plants wouldn't be able to reproduce with a weed so the risk should be minimal to non existant.

 

[Jack the Stri]

For starters, prokaryotes are single-celled organisms and thus by definition any transfer of a gene will result in that gene being present in all its progeny. For eukaryotes, this is much less straightforward. In addition, prokaryotes have certain mechanisms of gene transfer (independent of viruses) that we do not.

As for engineering plants, the most obvious way of giving rise to superweeds is through cross-pollination of same-species plants (how a native species of a crop suddenly becomes a weed is beyond me). While in theory the possibility exists of a gene being transferred to a micro-organism, stably integrating into the genome and then repeating the process from micro-organism to weed, in practice this hasn't been know to occur outside very ideal laboratory conditions (at least not to my knowledge).
Super weeds do indeed rather stem from improper use of pesticides and improper management of GMO crops in general. Note that spread of the gene by cross-fertilising can also be prevented in this way.

 

[Uremove]

In chapter 1, it seems to me that he's doing away with "walls" that separate species because of gene transfer between specieis and quotes Daniel Drell from Science (2001 294:1634) saying "we can no longer comfortably say what is a species anymore." I am aware that horizontal gene trasnfers were present at the very beginings of life according to evolution but he seems to be indicating that this is happening even now and frequently...

I think you are right to be confused Routaran... Lipton is playing a bit hard and fast with the science here, to promote what comes down to "New Age" philosophy. Sure, there are issues about what exactly demarcates a species: Morphology? Genetic similarity? Sexual reproduction producing fertile offspring? Cladistic lineage?

There are also examples of transposons (transpoable elements) crossing between species, especially in bacteria (e.g. plasmids) and viruses. Temperate viruses integrate their DNA into the host, and some bacteria e.g. Agrobacteria tumafaciens transgenically infect oak trees with bacterial DNA (to form galls).

However, that does not mean that it's all one happy co-operative gene swapping party, and that there are no longer any "walls" between species! Even among bacteria, plasmids (e.g. for antibiotic resistance) are passed most often between related organisms. However, successful genes will proliferate wherever they can! It is newsworthy when they cross species, as this gives rise to newly resistant organisms (like MRSA or VRE). More complex (i.e Eukaryote) organism species very rarely swap DNA, and competition between genes, organisms, groups of organisms etc. is still the driving force behind evolution. Limited resources mean only the most competitive will survive! Co-operation (mutualism) is a strategy used to successfully compete, but it can also turn into successful exploitation (i.e. parasitism or predation) very easily. Evolution is amoral and dispassionate!

So, I would advise approaching Lipton with some scepticism - he is selling an ideology based on the "power of belief" and the value of co-operation, not exclusively motivated by the scientific evidence!

 

[Routaran]

Thanks for the information Jack & Uremove. I'm still reading his book, had to take a few weeks off as i was out of town. I'm sure i'll have more questions given what I've read from chapter 1.

 

[Proton Soup]

regarding gene transfer with viruses, if the virus can transfer it's genes to us, does that mean that we also transfer our genes to it (uses our machinery to replicate itself)? if so, that would open up a mechanism for two species to swap genes if they are similar enough to be infected by the same virus.

and if I'm reading this right, the tyrosine hydroxylase gene in toxoplasma is more similar to the rat gene (it's more natural host) than the human gene. that might indicate the gene was stolen from rats rather than toxoplasma evolving its own version of hydroxylase to do the job.

http://www.plosone.org/article/info:doi/10.1371/journal.pone.0004801

 

[Uremove]

regarding gene transfer with viruses, if the virus can transfer it's genes to us, does that mean that we also transfer our genes to it (uses our machinery to replicate itself)? if so, that would open up a mechanism for two species to swap genes if they are similar enough to be infected by the same virus.

and if I'm reading this right, the tyrosine hydroxylase gene in toxoplasma is more similar to the rat gene (it's more natural host) than the human gene. that might indicate the gene was stolen from rats rather than toxoplasma evolving its own version of hydroxylase to do the job.

http://www.plosone.org/article/info:doi/10.1371/journal.pone.0004801

Yes, certainly viruses like adenovirus have been used to carry human genes and incorporate them into the human genome (e.g. in the treatment of Cystic Fibrosis). However, I don't know how often wild viruses would pick up host (e.g. human) genes and transfer them to another host. Space on the genome of an effective pathogenic virus is limited!

Thanks for the paper PS! Toxoplasma trophozoites survive host defenses by going intracellular, and the bradyzoites can be found encysted in any tissue (In the brain it can change the rat/mouse hosts behaviour by secreting neurotransmitters (hence precursors like L-DOPA), to make the mouse want to get eaten! (Toxoplasma reproduces sexually in predators like the cat).

However I'm not sure how it could pick up genes from the rat host. The Toxoplasma DNA (inside the nucleus) never leaves the cell - the T. gondii trophozoites get phagocytosed into a vacuole inside the host cell. Likewise the host DNA never gets near the Toxoplasma cytoplasm - so its hard to think of a mechanism by which T.gondii could pick up host genes.

I think the conserved similarity of the TyrH genes is more likely to be a case of mimicry (and convergent evolution), to do with transcribing into enzymes that have functional and structural similarities to the host enzymes, so as to minimise an immune response... but the similarity is certainly interesting, and a puzzle!