What about those jumping genes?

crash wrote: But what about those mariner elements? Maybe transposons (on steroids?) are the mechanisms you're looking for. If they work for genes, then why not genomes? The OP article speaks to a whole genome jumping from prokaryotes to eukaryotes. That makes a jump from insects to humans look trivial by comparison. Do you think they should? I do.”HM

Back to the same problems with naked DNA wandering around an organism's body. If a retrovirus is the simplest possible chemical structure that can get DNA from one cell to another reliably, the idea of naked DNA doing it seems unfeasible. Yeah, I do, too. For right now I think the problem is that HGT, if it's found to be common, is going to cast a lot of doubt on constructed phylogenies. Possibly a lot more doubt than is justified. No reason to stop looking for HGT, of course, but it's a good reason to refrain from a conclusion of HGT until one is very, very sure.

Naked DNA transfer is an interesting concept. Do you know of any mariner elements or transposons (if they are categorically different) that are able to operate apart from viral activity?”HM

I'm afraid I don't.

After having read the brief "news report" in New Scientist, I tried to track down the paper. I haven't had any luck.Do you have a link?If Andy Brass et. al. weren't able to publish their results, the tsetse/human HGT thing isn't worth discussing. You seem a bit confused. A mariner element is a transposon.maTA Clade of Transposons Intermediate Between mariner and Tc1 | Molecular Biology and Evolution | Oxford Academic Mariner elements are very small ... and share "low overall sequence identity" between species. Given this low sequence identity, it doesn't seem likely that Mariner sequences transfer "whole" to their host. Just to be clear. Transposons are similar to viruses, but it isn't fair to say that they "operate (with) viral activity". Transposons may confer benefit to their hosts, but it is generally thought that they are selfish DNA parasites.Transposons notoriously confer antibiotic resistance (and that is of benefit to the host) and they may have evolved into useful cellular "tools" for eukaryotes (telomerase and RAG1/RAG2). Transposons link. We are well aware of the mechanism for Class II TE transposition. Are you suggesting that a Class II TE (mariner) is responsible for moving an entire tsetse fly genome into a host?If you are able to provide support for that assertion, I would like to see it.Edited by molbiogirl, : No reason given.

molbiogirl asks: Only the one I posted to the abstract of the article. But I have a hard copy of the article somewhere in my files (I'm watching the Seahawks right now so I'm going to go dig for it). Thanks. I wasn't entirely sure. Thanks again. With you and crashfrog around I'll finally get things straight. No. Only fly genes. The only time I referenced whole-genome transfer was with respect to the OP artcile.”HM

From the article you cited: The author is pointing out that flies and humans have the mariner gene in common. Not that a fly gene is in the human genome.Gueiros-Filho F J, Beverley S M. Science. Trans kingdom transposition of the Drosophila element mariner within the protozoan Leishmania 1997;276:1716-1719. HGT is just interspecific transfer of DNA. Here's how HGT happens in prokaryotes: In other words, the fly and the human could have gotten the mariner TE from some common bacterial virus.Edited by molbiogirl, : fixed grammar

molbiogirl,Thank you for that contribution. I think what you have written above pretty much dispells my fantasy about tsetse-fly genes hopping over into the human genome. It was fun while it lasted, but your argument is compelling....So much for genetic transmorgrification.”HM

Seconded. A fascinatingly informative series of posts. Kudos!

I use a lot more than faith for debating creationism at EvC, in fact a lot more non-faith arguments for my ideology. Just as in secularist arguments I'm constantly required to document things etc just like you people are. This thread may not be the place to debate this and I won't because I'm not capable, but I grab onto all I can which supports my ideology to any degree. So if HGT should become imperically substantiated I still understand it as a problem for accredited science creationists to address. Frankly as a Biblical creationist I'm pleased to see that it is debatable.

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BUZSAW B 4 U 2 C Y BUZ SAW.
The immeasurable present is forever consuming the eternal future and extending the infinite past.

FYI, buz.HGT happens all the time.In bacteria and invertebrates.The only thing that was "debatable" on this thread was the transfer of eukaryotic DNA. And that was mostly just a misunderstanding. Turns out no fly genes were found in the human genome.Btw. Thanks Crash. Thanks HM. My pleasure.

OK Mobiogirl, thanks. Perhaps then so long as it's not observed in higher life forms CF and HM are right that it has little or no relevance to the creationism/evolution debate.

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BUZSAW B 4 U 2 C Y BUZ SAW.
The immeasurable present is forever consuming the eternal future and extending the infinite past.

Buz, HGT has happened in eukaryotes.The mitochondria.The chloroplast.Telomerase.RAG1 and RAG2 (important to antibodies and T cells).And that's just off the top of my head.Were I to research the question a bit, I am certain I could provide further examples of HGT in eukaryotes.

molbiogirl, you wrote: You and crashfrog seem to be astute in this business of HGT. I am neither astute nor in the business, but I read enough about it to be dangerous (at least to my own credibility). I have been reading Frederic Bushman's Lateral DNA Transfer/Mechanisms and Consequences (2002), in which he asserts "Our own DNA is a complex composite of imported sequences and mobile genetic parasites..." (p. xiii), and he speaks of "genes floating on a sea of retrotransposons" (pp. 239-275). Boy, does that ignite my imagination!Bushman uses the term "lateral DNA transfer" instead of HGT. Have either of you read his works? He appears to be a leader in this area at the Salk Institute.In Chapter 19 of his book he pursues the question: "DNA Transposons of Eukaryotes: Mariners Sailing to Survive?" In that pursuit he observes (p. 282): "Consider the cecropia family of Tc1/mariner elements, named for the giant silk worm moth Hyalophora cecropia, in which the first family member was found (Fig. 9.7) [see below]. Members of this family have been found in insects, flatworms, a hydra, and humans." "Figure 9.7. Sequence relationship among mariner elements of the cecropia subfamily. Note that a human element clusters with several insects, whereas a prosimian sequence clusters in a different part of the tree with other insects." (p. 282)I don't know, crash and molbiogirl, those bug genes look pretty jumpy to me.”HM

But where did Hyalophora cecropia get the mariner element?It was first identified in a moth, but no one (that I've found) indicates where this transposon originated.Btw. Transposons are 45% of your genome.