Horizontal transmission of a transposon in animal species

Here is the core of the article, in my opinion:

The fact that invasive DNA was seen in a bush baby but not in any other primates, and in a tenrec but not in elephants, hints that something more exotic than standard inheritance is going on.

However, this patchy distribution by itself does not rule out the traditional method, as some of the species could have lost the transposon DNA throughout evolutionary history.

So the team looked at the position of the hAT transposon – if it had been inherited from a common ancestor it would have been found in the same position, with respect to other genes, in each species. But they could not find a single case of this.

Since first entering the genome, the hAT has been able to reproduce dramatically – in the tenrec, 99,000 copies were found, making up a significant chunk of its DNA. Feschotte speculates that this must have had a dramatic effect on its evolutionary development.

“It’s like a bombardment”, he says. “It must have been evolutionarily significant because the transposon generated a huge amount of DNA after the initial transfer.”

Feschotte says he expects many more reports of horizontal gene jumping. “We’re talking about a paradigm shift because, until now, horizontal transfer has been seen as very rare in animal species. It’s actually a lot more common than we think.”  New Scientist

“More” is probably a good bet, all right, but horizontal transmission of genes is still not all that common in animals, so far as we can tell.  Still, 99,000 copies is bound to have made a difference in the evolution of the tenrec.

I thought the story itself was interesting, but it also has elements in its discovery that demonstrate how out-of-the-ordinary animal genetics can be and is discovered.  IDists sometimes like to point to the fact that this or that scientist agrees that design could be detected. 

But that’s their entire problem, it could be detected and it never is.  Meanwhile, science continues to find “non-canonical” changes and evolutionary patterns, such as this gene being laterally transferred into animal genomes.  It is entirely a matter of what has evidence and what does not.  Vertical transmission is by far the dominant form of gene transmission in, say, vertebrate species, as indicated by both conserved genes and by the lack of commonality after taxa diverge.  Horizontal transmission occurs, and is identifiable by its “lawfully accidental” appearance in unrelated species, as well as by the fact that the gene is not found in the same places in the genomes of the animals having a particular gene.

Now if we could ever find the commonality of authorship in any evolutionary development, such as older IDists predicted, ID would at last have some evidence in favor of it.

Advertisements
Explore posts in the same categories: News

Tags: , ,

You can comment below, or link to this permanent URL from your own site.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s


%d bloggers like this: