[sci.astro] DNA for interstellar messages

bs_wab@ux63.bath.ac.uk (Bains) (07/01/88)

Around the end of my undergraduate career I remember reading a paper
on the possibility of using DNA sequences for interstellar communication.
The idea was that you launched your message into space as a virus,
and it replicated itself wherever it landed. As only one virus needed
to 'get through' to spread the message this meant that a few tonnes of
virus could be as effective as gigawatts of maser beams. The authors
searched the sequence of a gene from a bacteriophage (Phi-X-174 I
think) for evidence for a message, (but fairly obviously found none:
if they had, I would not need reminding of the details!)

Or so the theory went. While full of rather substantial holes, it
might be more reasonable when combined with recent discoveries of
'catalytic RNA', and I would like to track down the paper to follow
this up. It was published before summer 1979, and I think in ICARUS.

Has anyone a) come across this paper before or b) come across similar
ideas anywhere else?

Many thanks for your help.

William Bains     
Department of Biochemsitry 
University of Bath
Claverton Down
Bath BA2 7AY
UK

ralf@b.gp.cs.cmu.edu (Ralf Brown) (07/03/88)

In article <2743@bath63.ux63.bath.ac.uk> bs_wab@ux63.bath.ac.uk (Bains) writes:
}Around the end of my undergraduate career I remember reading a paper
}on the possibility of using DNA sequences for interstellar communication.

}Has anyone a) come across this paper before or b) come across similar
}ideas anywhere else?

I remember reading (circa 1981/82) about a virus whose DNA had a sequence
which coded for THREE different proteins, depending on whether one started
reading at base N, base N+1, or base N+2.  (there are three bases per amino
acid of the protein).

One of the suggested explanations was that it might be just such a message,
as it was considered unlikely for such a DNA sequence to evolve by itself.  
-- 
{harvard,uunet,ucbvax}!b.gp.cs.cmu.edu!ralf -=-=- AT&T: (412)268-3053 (school) 
ARPA: RALF@B.GP.CS.CMU.EDU |"Tolerance means excusing the mistakes others make.
FIDO: Ralf Brown at 129/31 | Tact means not noticing them." --Arthur Schnitzler
BITnet: RALF%B.GP.CS.CMU.EDU@CMUCCVMA -=-=- DISCLAIMER? I claimed something?

bilbo@pnet02.cts.com (Bill Daggett) (07/04/88)

bs_wab@ux63.bath.ac.uk (Bains) writes:
>Around the end of my undergraduate career I remember reading a paper
>on the possibility of using DNA sequences for interstellar communication.
>The idea was that you launched your message into space as a virus,
>and it replicated itself wherever it landed. As only one virus needed
>to 'get through' to spread the message this meant that a few tonnes of
>virus could be as effective as gigawatts of maser beams. The authors
>searched the sequence of a gene from a bacteriophage (Phi-X-174 I
>think) for evidence for a message, (but fairly obviously found none:
>if they had, I would not need reminding of the details!)

Maybe it has worked...  Maybe WE are the message!  :-)

Bill

UUCP: {ihnp4!scgvaxd!cadovax rutgers!marque}!gryphon!pnet02!bilbo
INET: bilbo@pnet02.cts.com
* Sometimes The Dragon Wins! * Still looking for the best Amiga BBS
software to resurrect Bilbo's Hideaway on - but not holding breath!

jwm@stdc.jhuapl.edu (Jim Meritt) (07/06/88)

In article <4719@gryphon.CTS.COM> bilbo@pnet02.cts.com (Bill Daggett) writes:
}bs_wab@ux63.bath.ac.uk (Bains) writes:
}>Around the end of my undergraduate career I remember reading a paper
}>on the possibility of using DNA sequences for interstellar communication.
}
}Maybe it has worked...  Maybe WE are the message!  :-)


So thinking of the spiritualists,
the medium is the message?


Disclaimer: Individuals have opinions, organizations have policy.
            Therefore, these opinions are mine and not any organizations!
Q.E.D.
jwm@aplvax.jhuapl.edu 128.244.65.5  (James W. Meritt)

powi@ur-tut (Peter Owings) (07/06/88)

In article <2743@bath63.ux63.bath.ac.uk> bs_wab@ux63.bath.ac.uk (Bains) writes:
>
>Has anyone a) come across this paper before or b) come across similar
>ideas anywhere else?
>
	Well, I haven't heard anything about this paper, but one scientist
not far from you takes this kind of thing very seriously.  I was fortunate
enough to have several conversations with Sir Fred Hoyle when he visited
the University of Rochester.  If there is anyone who has written about 
stuff like "Bacteria From Space", Sir Fred has.  You might try looking at
a book called _Grains_to_Bacteria_.  The only problem with this book is
that it is very technical, going into spectral observations of interstellar
particles.
	But, if you want someone who has put a lot of thought into this,
I highly recommend Sir Fred.  I don't think that he is still teaching at
Cambridge, but he is still around there somewhere.

Peter...


>Many thanks for your help.
>
	's alright,

>William Bains     

	Peter Owings
	University of Rochester
	"The Cold and Distant Outpost, USA"

flash@ee.qmc.ac.uk (Flash Sheridan) (07/06/88)

In article <2244@ur-tut.UUCP> powi@tut.cc.rochester.edu.UUCP (Peter Owings) writes:
>In article <2743@bath63.ux63.bath.ac.uk> bs_wab@ux63.bath.ac.uk (Bains) writes:
>>
>	Well, I haven't heard anything about this paper, but one scientist
>not far from you takes this kind of thing very seriously.  I was fortunate
>enough to have several conversations with Sir Fred Hoyle when he visited

Remember, on this issue (_not_ astronomy) Hoyle is a crank.  I'm not saying
he's wrong, but he is a crank.  I've heard him lecture on it; he
misrepresents probability theory in order to show that evolution is
impossible.

From: flash@ee.qmc.ac.uk (Flash Sheridan)
Reply-To: sheridan@nss.cs.ucl.ac.uk
or_perhaps_Reply_to: flash@cs.qmc.ac.uk

bs_wab@ux63.bath.ac.uk (Bains) (07/06/88)

In article <2244@ur-tut.UUCP> powi@tut.cc.rochester.edu.UUCP (Peter Owings) writes:
>>
>      ... I was fortunate
>enough to have several conversations with Sir Fred Hoyle when he visited
>the University of Rochester.  If there is anyone who has written about 
>stuff like "Bacteria From Space", Sir Fred has.  You might try looking at
>a book called _Grains_to_Bacteria_.  The only problem with this book is
>that it is very technical, going into spectral observations of interstellar
>particles.
>	Peter Owings
>	University of Rochester
Ah, not quite what I had in mind because
i) The interstallar grains that Hoyle was concerned about were meant to be
the remains of entire organisms (if I understand Hoyle's ideas right,
which I quite possibly do not), not of 'pure' message. If you use an entire
organism as a messenger, then you have the problem of how to stop your
message evolving into meaningless garbage. (The same problem attends the
idea put forward in a previous posting (sorry, I don't have it in front
of me) that such a message exists and 'we are that message'. Apart from
anything else, which 'we'? There is about 1% genetic difference between
different individuals, so which 'us' is the right message? But I digress.)
ii) If Hoyle is right, and a substantial amount of interstellar dust is
actually of biological origin, it would mean that our hypothetical
communicators would have had to dismantle their entire solar system, maybe
their entire globular cluster, just to send their message out. This seems
a little entreme.
iii) Hoyle's data are EXTREMELY shakey! His 'matching' between interstellar
IR spectra and biological sample spectra are essentially 'fudge-it-till-
it-fits' excercises, with different bacteria and protein molecules being
added to his 'biological' sample until he got the right spectra. As with his
advocacy of the 'steady state' theory, Hoyle's insistance in this hypothesis
appears driven more by his dislike of creationists than by scientific
rigour (if life is generated in outer space, then the chances that it arose
spontaneously are much greater than if it has to arise on Earth, as
there is much MORE space than Earth). His idea that the archeopteryx fossil
is a fake has similar motivation, apparently (according to a dinosaur
fanatic who has heard him speak ont eh subject). 

ethan@ut-emx.UUCP (Ethan Tecumseh Vishniac) (07/06/88)

In article <2244@ur-tut.UUCP>, powi@ur-tut (Peter Owings) writes:
> In article <2743@bath63.ux63.bath.ac.uk> bs_wab@ux63.bath.ac.uk (Bains) writes:
... A bunch of stuff about using DNA as a kind of replicating message
carrier.
> >Has anyone a) come across this paper before or b) come across similar
> >ideas anywhere else?
> >

First, it seems to me that dropping a replicating bit of DNA into someone
else's biosphere is indeed a message of sorts...like dropping a bomb on
their house.  Regardless of contents it is an extremely hostile act.

> 	Well, I haven't heard anything about this paper, but one scientist
> not far from you takes this kind of thing very seriously.  I was fortunate
> enough to have several conversations with Sir Fred Hoyle when he visited
> the University of Rochester.  If there is anyone who has written about 
> stuff like "Bacteria From Space", Sir Fred has.  You might try looking at
> a book called _Grains_to_Bacteria_.  The only problem with this book is
> that it is very technical, going into spectral observations of interstellar
> particles.

Hmm.... there is one other problem with the book.  Almost all experts on
the interstellar medium (actually all but Hoyle and Wickramsinghe) consider
their interpretation of the spectral features to be ludicrous.
It's not my field, but the criticisms I've heard sounded devastating.

-- 
 I'm not afraid of dying     Ethan Vishniac, Dept of Astronomy, Univ. of Texas
 I just don't want to be     {charm,ut-sally,ut-ngp,noao}!utastro!ethan
 there when it happens.      (arpanet) ethan@astro.AS.UTEXAS.EDU
    - Woody Allen            (bitnet) ethan%astro.as.utexas.edu@CUNYVM.CUNY.EDU

wooding@daisy.UUCP (Mike Wooding) (07/06/88)

In article <4719@gryphon.CTS.COM> bilbo@pnet02.cts.com (Bill Daggett) writes:
}bs_wab@ux63.bath.ac.uk (Bains) writes:
}>Around the end of my undergraduate career I remember reading a paper
}>on the possibility of using DNA sequences for interstellar communication.
}
}Maybe it has worked...  Maybe WE are the message!  :-)

 Do you suppose "they" knew about error correcting codes? :-)

 m wooding

dlp@ih1ap.ATT.COM (Random @ rebmA) (07/06/88)

> 
> bs_wab@ux63.bath.ac.uk (Bains) writes:
>>Around the end of my undergraduate career I remember reading a paper
>>on the possibility of using DNA sequences for interstellar communication.
You don't mention when this paper was written, but I recall a similar
scenario. Check out 'The Andromeda Strain' then 'Mutant 59, The Plastic
Eaters' by the same author (whos name escapes me).

	Random

watson@ames.arc.nasa.gov (John S. Watson) (07/07/88)

> Around the end of my undergduate career I remember reading a paper
> on the possibility of using DNA sequences for interstellar communication.
> The idea was that you launched your message into space as a virus,
> and it replicated itself wherever it landed. 

This reminds me of the book CONTACT by Carl Sagen, where the scientist 
looks for a coded message from the creator(s) of the universe
in the number PI, i.e: 

        3.1415...IFYOUCANREADTHISPHONEHOMEET...234328...

I alway think of this whenever I see images of the Mandelbrot set and
realize thoughs incredibly beautiful and complex pictures were made 
with iterations of the simple equation  Xnew = Xold**2 + Constant 
(all complex numbers).

Maybe our creator(s) stuck a message somewhere in our DNA, "Greetings",
"may the Force be with you", "Have a Nice Day" or maybe a 
copywrite notices and patent numbers. :-)

-- 
John "Metaman" Watson, IBM heir in hiding     ARPA: watson@ames.arc.nasa.gov
NASA Ames Research Center                     UUCP:  ...!ames!watson
Any opinions expressed herein are solely the responsibility of the
author and do not represent the opinions of NASA or the U.S. Government, yet.

dalex@eleazar.dartmouth.edu (David Alexander) (07/07/88)

In article <1027@ih1ap.ATT.COM> dlp@ih1ap.ATT.COM
                                                (Random @ rebmA) writes:
> Check out 'The Andromeda Strain' then 'Mutant 59, The Plastic
> Eaters' by the same author (whos name escapes me).

Michael Crichton.



****************************************************************************
* Per lor maledizion si non si perde           Dave Alexander              *
* Che non possa tornar l'etterno amore         dalex@eleazar.dartmouth.edu *
* Mentre che la speranza ha fior del verde     *****************************

willner@cfa250.harvard.edu (Steve Willner P-316 x57123) (07/07/88)

From article <2244@ur-tut.UUCP>, by powi@ur-tut (Peter Owings):

> I was fortunate enough to have several conversations with Sir Fred
> Hoyle when he visited the University of Rochester.  If there is
> anyone who has written about stuff like "Bacteria From Space", Sir
> Fred has.  You might try looking at a book called
> _Grains_to_Bacteria_.  The only problem with this book is that it
> is very technical, going into spectral observations of interstellar
> particles.

Sorry, but I doubt that's the only problem.  (Some might say it's not
a problem at all.)  Though I haven't read this particular book, I am
familiar with the Hoyle and Wickramasinghe papers published in
journals.  Although the observed interstellar spectra and the
polysacccharide or "bacteria" spectra look superficially very
similar, a closer look reveals that the disagreement is in the
_wavelength_ axis.  That is, the interstellar spectral features just
do not have the wavelengths predicted by the Hoyle/Wickramasinghe
model.  While I would not consider a disagreement in the strengths of
the various features a serious problem, the wavelengths are a
different matter.  Wavelengths ought to depend mainly on the kind of
material producing the features, and a discrepancy in wavelength
strongly suggests that the identification is wrong.  Moreover, there
are far more plausible identifications for most of the observed
spectral features.
-- 
Steve Willner            Phone 617-495-7123         Bitnet:   willner@cfa
60 Garden St.            FTS:      830-7123           UUCP:   willner@cfa
Cambridge, MA 02138 USA                 Internet: willner@cfa.harvard.edu

dietz@gvax.cs.cornell.edu (Paul F. Dietz) (07/08/88)

From article <2244@ur-tut.UUCP>, by powi@ur-tut (Peter Owings):
> I was fortunate enough to have several conversations with Sir Fred
> Hoyle when he visited the University of Rochester.  If there is
> anyone who has written about stuff like "Bacteria From Space", Sir
> Fred has.  You might try looking at a book called
> _Grains_to_Bacteria_.  The only problem with this book is that it
> is very technical, going into spectral observations of interstellar
> particles.

You might want to read Shapiro's (I believe that's the name) description
of H&W's work in the book "Origins".  The description of H&W's
methodology is fascinating.  They apparently took some organic
spectra and ran them through a blurring procedure, then remarked
at how the resulting spectra resembled that of interstellar grains.

Shapiro gave an analogy to illustrate the validity of this procedure.
Suppose you have a picture of a man taken on a foggy night.  You claim
this is actually a picture of President Reagan.  To support your
claim, you take a picture of Reagan and blur it, then note the
similarities (for example, in both pictures the figures have two arms
and two legs).

Nature wised up after a while and stopped accepting their papers.

	Paul F. Dietz
	dietz@gvax.cs.cornell.edu

alaa@pedsga.UUCP (07/08/88)

I read about the subject in Sir Fred Hoyles book "The Intelligent Universe".
Although I am no expert in the subject (or maybe because of that), the
book seemed fascinating. However I should read some critique of the theories
presented in it to be able to form my own opinion on the matter. In any
case I recommend reading that book.

As for the DNA messages, I think the messages were sent via microwave
or lazer or some form of signals duplicating DNA codes. And not by
sending an actual virus (friendly earthlings would'nt do a thing like
that, would they? I mean they have not confirmed that there is some
one there to harrass yet :-;  )

--Alaa			...!petsd!pedsgd!alaa

dlp@ih1ap.ATT.COM (David Lee Pope @ rebmA) (07/08/88)

I couldn't resist! This is by far the most creative misspelling
I have ever seen. :^)

	Random

bilbo@pnet02.cts.com (Bill Daggett) (07/10/88)

bs_wab@ux63.bath.ac.uk (Bains) writes:
>i) The interstallar grains that Hoyle was concerned about were meant to be
>the remains of entire organisms (if I understand Hoyle's ideas right,
>which I quite possibly do not), not of 'pure' message. If you use an entire
>organism as a messenger, then you have the problem of how to stop your
>message evolving into meaningless garbage. (The same problem attends the
>idea put forward in a previous posting (sorry, I don't have it in front
>of me) that such a message exists and 'we are that message'. Apart from
>anything else, which 'we'? There is about 1% genetic difference between
>different individuals, so which 'us' is the right message? But I digress.)
Nothing is perfect.  I mean some message is better then no message and so far
we have no message.  The DNA transmitter may not be "intelligent" and it would
include ALL life and not just some "special" sentient creature dreaming of a
way to communicate with anther planet.  The point is you do not stop the
message from  evolving into menaingless garbage.  Meaningless garbage is
exactly what has created us for 5 billion years (or so).  If it is TRUE, does
the human species resemble the original DNA message transported through time
and space from so many distant places?  This is what I meant by WE (may be)
are the message.  It can't be whole.

As far as how a planet would transmit all its DNA stuff through space perhaps
when its star dies and novas the explosion rather then consuming the third
planet from the sun would break it up and spew it out into the cosmos to land
a tiny portion someday on another planet?  This was never the way I thought of
communicating with other life in the universe.  It sort of ruins Star Trek.

Bill

UUCP: {ihnp4!scgvaxd!cadovax rutgers!marque}!gryphon!pnet02!bilbo
INET: bilbo@pnet02.cts.com
* Sometimes The Dragon Wins! * Still looking for the best Amiga BBS
software to resurrect Bilbo's Hideaway on - but not holding breath!

king@client2.DRETOR.UUCP (Stephen King) (07/12/88)

In article <1027@ih1ap.ATT.COM> dlp@ih1ap.ATT.COM (Random @ rebmA) writes:
>You don't mention when this paper was written, but I recall a similar
>scenario. Check out 'The Andromeda Strain' then 'Mutant 59, The Plastic
>Eaters' by the same author (whos name escapes me).

_The Andromeda Strain_ was written by Michael Crichton.

_Mutant 59, The Plastic Eater_ (one of my favourite novels) was co-authored
by Kit Pedlar and Gerry Davis, known for the BBC series _Doomwatch_.

---Methinks the facts escape you---forgive spelling mistakes---SJ King---

ayermish@athena.mit.edu (Aimee Yermish) (07/15/88)

Besides the problems of not wanting to let loose a nasty evil killer
phage from hell on the nice friendly space aliens, there are some
realities that just don't make walkie-talkie-viruses the most
promising of methods.

1.  Why would you *want* to use DNA, which is not a particularly
obvious code, for communication with another planet?  Sagan squares
seem a lot more promising.  Remember that viruses are generally pretty
small and it's all they can do to contain their *own* coding
information, so huge quantities of interesting stuff are probably out
of the question.

2.  You're assuming that there are cells on the receiving planet that
can (a) be infected by the virus (tailspikes are pretty specific
enzymes, y'know) (b) replicate it (requires the presence of
machinery which can transcribe and translate the code, not to mention
the correct precursors) and (c) lyse it (probably the easiest step, if
you've gotten that far, but it still requires a susceptibility to
whatever protease the virus has).  Somehow I don't think that's a
terrific assumption to make.

3.  Unless you stuck the virus in some nice container, space vacuum
might well do nasty things to the virus.  But if you're sending a nice
container, why not put something more self-explanatory (like, say, a
picture) in it?

4.  Why send a single probe that moves slower than light and gets
stuck on asteroids and falls into stars and such when you can send a
electromagnetic radiation-type message?

5.  Speaking of electromagnetic radiation, there's an awful lot of it
out there in space with no atmosphere to protect you.  UV radiation
does bad things to DNA.  In particular, it dimerizes adjacent
thymidine residues, leaving you with something unreadable.  Here on
earth, the cells have evolved all sorts of complex mechanisms to find
and correct errors.  Viruses don't carry those mechanisms with them.

I'd think of some more, but I have to run.  Sorry to burst bubbles.

--Aimee
------------------------------------------------------------------
Aimee Yermish		ayermish@athena.mit.edu
MIT couldn't care less about anything I say. 
(as long as I finish that last paper...)

bs_wab@ux63.bath.ac.uk (Bains) (07/26/88)

In article <6211@bloom-beacon.MIT.EDU> ayermish@athena.mit.edu (Aimee Yermish) writes:
>1.  Why would you *want* to use DNA, which is not a particularly
>obvious code, for communication with another planet?  
That is one question I was hoping the original article might answer, but 
for starters, see 5 below.

>2.  You're assuming that there are cells on the receiving planet that
>can (a) be infected by the virus 
 ... and it can replicate and lyse. No I am not. i) The ORIGINAL PAPER
was talking about viruses, which is why I thought it dodgy. ii) Not all
viruses enter cells by such specific mechanisms as the well-known
bacteriophages: a membrane fusion mechanism could be much more general.
iii) I was not all that interested in viruses themselves anyway, but in
viroids, which appear to be self-replicating RNAs requiring only
RNA precursors to reproduce. The RNA strand is both message and polymerase.
So no host enzymes required. Actually, no host cell lysis required either
as the cell either dies from the metabolic effort of carrying all those
viroids around (which is apparently what happens to plant cells) or does not,
in which case it passes the viroid on vertically.
>
>3. .., space vacuum
>might well do nasty things to the virus.  
... but not to a viroid, which is a single chemical. (Not necessarily to
a virus either, in fact, as the ATCC can provide many of them freeze-dried
with 'keep cold' on the side.)

>4.  Why send a single probe that moves slower than light and gets
>stuck on asteroids and falls into stars and such when you can send a
>electromagnetic radiation-type message?

 ... because  ...

>5.  Speaking of electromagnetic radiation, there's an awful lot of it
>out there in space with no atmosphere to protect you.  UV radiation
>does bad things to DNA. 
 ... and to em signals too. The power required to send a recogniseable
electromagnetic signal half way across the galaxy is fantastic, and
you still run the risk that the receiver will not be listening at the right
time or on the right frequency. Both would be no problems to self-propagating
RNA. 
  The radiation damage to the chemical is a major problem, however. Whether 
it is less of a problem depends critically on how much material you launch, 
how much is needed on landing, interstellar UV and X-ray intensities and
radiation-sensitivity of your molecule. As this was a 'hey, has anyone
heard of this' search for a previously published paper, I have not
worked these points out! But you have hit a serious nail on the head
with this one. 
>
>I'd think of some more, but I have to run.  Sorry to burst bubbles.
>

No problem. The regular sound of bursting bubbles is what distinguishes
science from pseudoscience.

>Aimee Yermish		ayermish@athena.mit.edu

William Bains:  wbains@bionet-20.arpa, bs_wab@uk.ac.bath.ux63

eddy@boulder.Colorado.EDU (Sean Eddy) (07/28/88)

In article <2863@bath63.ux63.bath.ac.uk> bs_wab@ux63.bath.ac.uk (Bains) writes:
>iii) I was not all that interested in viruses themselves anyway, but in
>viroids, which appear to be self-replicating RNAs requiring only
>RNA precursors to reproduce. The RNA strand is both message and polymerase.

This is (unfortunately for the romantics of the "RNA world" hypothesis)
not correct. The replicase involved in viroid replication has not
been identified, to my knowledge. 
The known RNA catalytic activity of viroid RNAs
is limited to self-cleavage and such. (Unless you know
of something quite recent -- but here in the land of Tom Cech, 
such a discovery would have left the place in chaos...)

The only RNA-based "polymerase" in the literature so far is a derivative
of the _Tetrahymena_ self-splicing group I intron, which is capable
of rearranging ribooligonucleotides to a small extent
to make both longer and shorter products. 

- Sean Eddy
- Molecular/Cellular/Developmental Biology; U. of Colorado at Boulder
- eddy@boulder.colorado.EDU		!{hao,nbires}!boulder!eddy	
-
- "But the scientist is intensely religious -- he is so religious
-  that he will not accept quarter-truths, because they are an 
-  insult to his faith."
-                       - Sinclair Lewis, in _Arrowsmith_