Johnye writes:

Wouldn’t have known about AAV but for you and Dr. King. Thank you. Johnye

Johnye Ballenger, M. D., FAAP

Johnye writes:

Does this qualify as “gain of function”?

“According to Vandenberghe, generating novel infectious agents may raise some concerns, but several safety measures have been taken. For example, AAVs are not known to cause any diseases, and their replication machinery is crippled prior to their use in gene therapy.”

Luk Vandenberghe’s work at MEEI, HMS, Boston.

Johnye Ballenger, M. D., FAAP

Robin writes:

Gain of Function

It is the nature of ALL biological organisms in the course of their evolutionary history to be selected for gain of function. Otherwise we’d still be a soup of miscellaneous organic macromolecules, or perhaps one giant slime mold. Sans natural gain of function on the part of our adversaries, we would not have innate defences; without the specific instance of  recombination involving the syncitin gene, there may still be prototheria (egg laying mammals) and metatheria (pouched mammals) but no eutheria (placental mammals).

Isolation from gain of function over the course of millennia may have less than salutary effects: the Native Americans / First Nations were well nigh eradicated by smallpox, measles, etc.

If we don’t look into “gain of function” and deal with it first, sooner or later Nature will do so with no compunctions whatsoever about any gain of function. We need look no further than the indigenous peoples of the Americas or the recent Ebola in Africa to get an idea of what to expect in such circumstances.

Sooner or later, it’s gonna happen, whether we’re ready or not.

Stefan writes:

Dear Masters of the ScienTWIVic Universe,

I have a great paper suggestion for TWIV from Eckard Wimmer’s group: “Large-scale recoding of an arbovirus genome to rebalance its insect versus mammalian preference” . It has everything the TWIV heart desires, an awesome story with genius factor, insect biology (Dixon will be delighted), the dinucleotide codon bias only Kathy can explain , real virus titrations by plaque assay (I am sure Vincent will not leave this uncommented) and plenty more …

The virus deoptimization and recoding of viral genome goes back to TWiV 2 (Polio is not dead), refreshed in TWIV 236 (Flu gets the VIP treatment) and now for a double:  dengue (Shen et al 2015, PNAS ) and VSV (Wang et al 2015, mBio).  What is the TWIV-think-tank opinion on this ? How the hell does this work, why are these deoptimized viruses attenuated? Will codon recoding become the vaccine strategy for the future? Could we even feed insects a human-deoptimized virus and use the natural vector to deliver an attenuated virus as a vaccine?

Thank you so much for all you do for virology and science communication. I admire how you guys keep this going.

It is mid June and the temperature in Luebeck (North Germany) is 21˚C (69F) and not a cloud in the sky (for a change). Local forecast are a few Measles and with a slight chance of MERS from the East.

Always a fan,


P.S. we have a great B.Sc. M.Sc. programs with great focus on virology and infectious diseases: Infection Biology (English) and Molecular Life Science (English starting WS15/16), great curriculum, no tuition fees, and yes we do plaque-assays in practicals 😉

Infection Biology (English)


Molecular Life Science (English starting WS15/16)

Prof. Dr. Stefan Taube

Professor for Structural and Molecular Virology

University of Lübeck

Institute for Virology and Cell Biology

23562 Lübeck


Bill writes:

A custom online crispr tool

what more to say chopchop…

Wink writes:

I enjoyed your discussion about infections leading to autoimmune diseases. Your Free-Lance Professor Condit kicked it off saying that narcolepsy after a certain influenza vaccine in certain populations was an example of that. Vincent gave the quintessential example of Rheumatic Fever. But there is one fairly well characterized example of this happening after a virus infection (although I am not well versed on the mechanism). About 10% of cases of Guillanne Barre Syndrome follow CMV infections and are probably due to antibodies raised against cytomegalovirus, but cross-reacting with human tissue.

Wink Weinberg, MD



Anthony writes:

Live animal markets in Minnesota: a potential source for emergence of novel influenza A viruses and interspecies transmission

# # #

On a separate, but related note:

Google Maps — New York City, live chicken market

Before dawn decades ago, while jogging on Paterson Plank Rd. in Jersey City (over Hoboken) I saw a flatbed truck filled with cages of live chickens.  The odor was powerful even some distance away.  I don’t know the origin or destination of the truck.  Certainly all along the route, dust and droppings were distributed.  Only some weeks ago I saw a similar truck during the day making its way through the residential streets of Union City.  This time, the cargo was rabbits.  If there is an outbreak of Avian Influenza that poses a danger to human health, the transportation of live poultry through the NY Metro area would seem to be a risk.


Mark writes:

Hi TWIVologists

Thank you Vincent, Kathy, Rich, and Alan for TWIV! I enjoy listening as commute to work on my bike. It’s great to still be able to keep up with virology break throughs and break outs!

I am writing to request you put me in contact with William in California (a letter from episode #348). I’d be extremely interested connecting with him about the idea of a TWIET (This Week in Ed Tech) podcast. The TWIV experience is enriched by each of your opinions, questions, and the discussions that result. I would be greatly enjoy jumping into this discussion with William. I left my postdoc in influenza research to join Sapling Learning, an EdTech company that designs and tailors online homework for college biology, chemistry, and physics classes.

Having mentioned postdocs, I wanted comment on the various discussions you’ve had about the academic track. I was involved in post-doc association at UT Austin, and was fortunate enough to attend the national postdoc association conference in 2013. My takeaways;

1) Even for all the postdocs at Tier 1 institutions most will not end up as faculty at Tier1 schools. This seemingly simple statement is something for every postdoc and PhD student to consider.

2) Since one is true, training for PhD students (and postdocs) should broaden their ability to work outside of academia. I came back to UT and initiated several programs to bridge the gap between our academic island and the local biotech and science companies that employ PhDs.

3) The economics of running a lab were highlighted by the keynote speaker that year, Dr. Paula Stephan. I suggest taking a look through her slides, focusing in on the “Economics of the postdoctoral position”, and in particular the costs of “Staffing of Labs. Basically postdocs are the cheapest form of lab laborers.

Just something to think about.

Best, Mark

Mark Collins, PhD

Alice writes:

Dr. R. — don’t know if anyone responded to William about his good podcast idea. I wanted to point out that, while “TWIET” is not patented, it is being used. Leo LaPorte has a podcast on his network called, “This week in Enterprise Tech,” which uses the acronym “TWIET.” Best, Alice

Bill writes:


I am a science guy totally hooked on twiv.  In another universe, I became a virologist, but here I deal with network security and the kinds of viruses that don’t make you sick, they make you unproductive.

But it is 32C here at the moment in Flemington NJ, and we’ve just had a summer cloudburst.  If you like this sort of weather, I strongly recommend that you check out:

a collation of worldwide lightning activity.  The current display in NJ is:

which looks like this:


The lightning strikes are computed and reported within a few seconds of the strike or strikes, and it is fun to watch a storm and see the actual location of the bolts.


Amanda writes:

Hi TWiV team,

Long time listener, sometimes writer. Sorry I’m a bit behind, but the part of Papua New Guinea (PNG) I live in has limited and expensive cellular internet only, making it difficult to stay caught up. As I was listening to the email from Robin and Alan’s comments on the GMO free / Kosher / Gluten Free salt it brought to mind a frustration of mine. I have long refused to buy anything that says GMO free on the packaging, as I see it as playing on people’s fears and lack of knowledge on the topic for a profit. But then I was diagnosed as celiac. So, I legitimately cannot eat a crumb of gluten. Now, everyone is jumping on these fad diets and going XYZ-free, which on one hand is nice, there’s more options for me at the store (at least in North America). BUT, it turns out that these fad dieters also tend to be the people who are antivax, anti-GMO, anti-science… Trying to find gluten free items that don’t have the ‘GMO-free’ stamp is becoming increasingly difficult and sometimes I am forced to buy. Especially here when gluten free items are few and far between. And every time I can’t help but feel a bit of outrage.

As always, thanks for the podcasts and all you guys do for science outreach. It’s currently 17°C and a bit cloudy in Goroka, PNG.

Ken writes:

The New York Times had a fascinating article on 600 years of weather reporting on a cave wall in China. Apparently, whenever there was a drought in the region, the people would go to the cave to collect water, and leave an inscription on the wall. There are inscriptions from 1520 through 1920 CE. Scientists correlated the inscriptions with an isotopic analysis of the cave stalagmites!

Maybe someday in the distant future, scientists will resurrect old TWIV episodes to study climate…


Snohomish, WA

Fair, 64F with expected high of 84F

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