Friday, May 22, 2015

I've been thinking...

That story about developing yeast that could make opiates reminded me today of the recent story about geeks interested in developing yeast that could make milk proteins.  In that post, I speculated about such yeast proliferating in the wild and having the potential to ruin fermented products.   Well, rather than cheese tainted home brewed beer, opiate tainted ones could be even worse.

Yeast is easy to work with for such wannabe DNA tinkerers, but doesn't the fact that it lives happily in the wild, floating invisibly around us, make the potential for its accidental release more of a concern than the escape of other micro-organisms?

Well, my point is not completely unfounded.  In a Popular Mechanics article "Better Beer from Genetically Engineered Yeast":
The ecological concern is more nuanced, Verstrepen says. Here, his main concern is the prospect of introducing non-yeast genes into a yeast, with the worry that these new, human-picked genes could be bred or passed on across yeasts in the outside world. "And this is a serious concern. You need to understand what you're doing, and make sure you're not going to accidentally confer some ecological advantage to the outside population," he says.
Even if these new yeasts were to escape, he explains, the chances of them out-competing other, wild yeast species—given that beer yeast is tailored to perform in a very unnatural environment—is unlikely, but certainly worth watching for.
I see that anti GM advocates are ahead of me, and that genetically modified yeast has already been used for lots of purposes, including drug production.  This article speculates on the possible health effects on humans getting an accidental GM modified yeast in their gut.  ( I assume that they don't actually normally take up residence there, but I'd have to read more about it.)

Going back to a science journal, I see a link to a paper in 1994 about an experiment to see if a GM modified yeast did well in a "natural" environment.   I wonder if such tests are required on all GM modified yeasts before they are used?

Curious minds - well mine, anyway - would like to know....


3 comments:

TimT said...

Like most GM fears it seems pretty unfounded. For instance, what kind of a drug baron is smart enough to genetically engineer a morphine-producing yeast but dumb enough not to ensure the yeast can't cross-breed to make sure competitors can't get hold of it? Mind you, given it is sometimes just about the quick buck....

It's also worth bearing in mind that these sort of yeasts would just be bred in laboratory conditions, stored in phials in the fridge, etc. And most commercial brewing yeasts are said to have lost the ability to interbreed anyway - they just clone themselves. Makes them much more predictable, albeit also more prone to infection.

Steve said...

Tim, I think the concern is not the drug baron doing the genetic engineering themselves, but getting their hands on the lab made morphine making yeast from a commercial facility that is using it. (Presumably, it could be easy for a lab technician wanting to make money to walk out of the factory with some to sell for a very large profit.)

Steve said...

I should also add that, while ever a commercial lab is using a GM modified yeast, we might expect them to have steps in place to prevent the ready distribution of the live yeast into the environment.

But if a yeast gets into the hands of drug barons, it's unlikely they'll care about biosecurity issues, except to the extent that it is not handed over to competitors too readily.