
Scientists have located an algal virus that attacks human DNA - johnloeber
http://www.newsweek.com/american-researchers-discover-stupidity-virus-283319
======
ChuckMcM
One of the interesting things about tap water is that it periodically suffers
from algae 'blooms' (which is addressed by chlorine but the remnants of the
algae persist. I've asked Dr Yolken for a copy of the paper and if they have
checked that vector. Once again I find myself thinking I should get a DNA
sequencer so that I could analyze my own tap water more quickly.

[1] Original paper --
[http://www.pnas.org/content/111/45/16106.abstract](http://www.pnas.org/content/111/45/16106.abstract)

~~~
Blahah
When the Oxford Nanopore MinION comes out of the early access trials, you will
actually be able to do this for a cost of somewhere around $1000.

~~~
kolev
Illumina already sells a $1,000-genome machine. By the way, what's happened
with the ambitious SV-based Halcyon Molecular, which was supposed to deliver a
$100-genome sequencer?

P.S. Halcyon has shut down 2 years ago [1].

[1] [https://gigaom.com/2012/08/19/halcyon-molecular-quietly-
shut...](https://gigaom.com/2012/08/19/halcyon-molecular-quietly-shuts-down/)

~~~
razzmataz
Actually, Illumina's $1000-genome machine is 10 machines, and the way you get
the $1000 genome cost is by running around 18000 samples thru in a year....
And when the bioinformatics folks talk about a '$1000 genome', they actually
mean the cost of reagents.

~~~
kolev
This is what I meant [1]. It seems that only a few Australian companies do
this for external parties for about $1,500/genome. I'm tired of waiting for
the price to get down and to be offered publicly - is it possible to do
personal sequencing somewhere in the US below $2,000? Is there another way? I
don't mind donating my genome if there are ways to get this cheaper (or free)
and do more if necessary.

[1] [http://systems.illumina.com/systems/hiseq-x-sequencing-
syste...](http://systems.illumina.com/systems/hiseq-x-sequencing-system.html)

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fchollet
92 volunteers, 43.5% were infected -> exactly 40 volunteers were infected, and
52 weren't. Then they claim to have found that the infected sample performed
"10% worse" on intelligence tests.

Intellectual performance follows a gaussian distribution. If you take two
random samples, one of 40 people, and one of 52 people, and you average the
IQs in each sample, the probability that you will find a deviation 10% or
greater one way to another is over 50%... in this particular case, to compute
the probability of the null hypothesis precisely we would need the exact
result distribution on the tests they used, but in any case, take these
results with a pinch of salt.

~~~
stillsut
I thought: E[IQ] = 100, SD[IQ] = 10 then SD (for n = 37) = (10 / sqrt(36)) =~
2

So a 10 point deviation between groups is 5 sd's, p <.001 ?

~~~
leeber
Guys, we're programmers here not statisticians:

def test():

... n1 = numpy.average(numpy.random.normal(100,15,52))

... n2 = numpy.average(numpy.random.normal(100,15,40))

... return abs(n1-n2) / ((n1+n2)/2.0)

...

>>> vals = [test() for i in xrange(0,1000)]

>>> numOver10 = len([v for v in vals if v > .1])

>>> numOver10

2

~~~
tomrod
Crucial in your code is the standard deviation of 15. Where is that coming
from?

Ah, I see. Standard IQ normalizations.

~~~
leeber
[http://en.wikipedia.org/wiki/Intelligence_quotient](http://en.wikipedia.org/wiki/Intelligence_quotient)

------
tokenadult
This is a preliminary research study and may not be replicated. Things I would
want to know, after a replication study is published, is what the effect size
is across more than one animal model (both mice and rats should be tried, and
different strains of inbred mice with known differences in cognitive
performance on mouse cognitive tasks should definitely be tried). I would also
want a broader survey of human patients from more different parts of the world
to see how many human beings show the same clinical sign the authors report
here. And I'd want some of the human surveys to include very young
participants, to see if rates of purported infection increase as human beings
age. Right now, if I were to bet on this, my bet is that this result doesn't
even replicate. (That's a reasonably good bet, as only about 50 percent of all
scientific first findings, even those that have been published in a peer-
reviewed journal, ever do replicate.)

------
tomrod
> Researchers found no connection between slower brain function and variables
> such as differences in sex, education level, income, race, and even
> cigarette smoking.

They have 92 observations. I don't think they have enough data to control for
these sufficiently.

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Gravityloss
If this is real and a cure can be developed, think about the huge free boost
it gives to humanity in total since it might affect such a large amount of
people. On the other hand, I'm skeptical. With such drastic effects, wouldn't
the evolutionary pressure for the immune system to deal with it have been
tremendous?

~~~
TeMPOraL
Since it apparently doesn't affect sexual performance much, would it?

Also it might be the case that the infection vector is something relatively
new to us, something not present in the ancestral environment, like the tap
water idea of ChuckMcM -
[https://news.ycombinator.com/item?id=8608780](https://news.ycombinator.com/item?id=8608780).

~~~
AnimalMuppet
If it lowers intelligence and/or increases response time, it could affect
survival. It's not enough to be able to reproduce, you have to live long
enough to do it. So, yes, it would be subject to selection pressure.

~~~
pm90
Subject to pressure yes, annhilated by it, no. Does natural selection really
affect human population anymore? Genuinely curious, because what I see is that
the the people with tons of kids aren't usually the most intelligent one
(anecdotal evidence, of course)

------
oldspiceman
Reminds me of that cat virus linked to schizophrenia.
[http://en.wikipedia.org/wiki/Toxoplasma_gondii](http://en.wikipedia.org/wiki/Toxoplasma_gondii)

~~~
jarin
It's not a virus, it's a protozoan.

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blackbagboys
I suppose it would be a gross overreaction to rush out and try to get to
tested for this virus?

~~~
gwern
Yes. I'm not sure how you would either, unless you have access to a
genetics/microbiology lab and the expertise to cluster and interpret the data.

------
KerrickStaley
The researchers at this lab do lots of other interesting work:
[http://stanleylab.org/staff/](http://stanleylab.org/staff/)

(Or at least things that have been hot on HN lately, e.g. Toxoplasmosis)

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inglondon
I posted this a few days ago here:
[https://news.ycombinator.com/item?id=8583393](https://news.ycombinator.com/item?id=8583393)

------
twic
So they tested a bunch of people, and found that those of them who regularly
eat algae are a little less intelligent. Well, yeah.

~~~
DanBC
The Japanese regularly eat algae. Are they less intelligent?

~~~
jacquesm
Sweetwater algae vs saltwater algae is quite a difference.

------
shkkmo
That is absolutely terrifying. I don't want to know what applications the DOD
comes up with once the vector is known...

~~~
bdamm
Yeah, I will never again eat "Made in China" candy.

