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Greenwolf103
07-04-2007, 08:30 AM
I have a character with a strong medical background, who works for the FBI (please spare me the Sully comparisons -- the similarities of my 2 characters creeps me out enough). She is examining an alien baby that was discovered at a crash site. In this story, aliens were long ago discovered and the FBI has been secretly analyzing them and testing them.

My character has a long detailed list of alien genetics, physiology, etc., so she has something to compare her notes to. What I need is some medical terminology she can use in a short piece of dialogue to show she knows her stuff when describing how she's discovered HUMAN genetic traces and HUMAN DNA sequences in the alien baby. The baby is an alien/human hybrid, but she doesn't know that.

If anyone has any info on what she could say, I'd sure appreciate the info. Thank you. :)

Selimthegrim
07-04-2007, 08:40 AM
Well, I forget who said it, but somebody said that it would be more likely that humans could mate with flowers than with aliens, because at least humans and flowers evolved on the same planet. However, if you want to introduce a dash of pseudoscience into a passage concerning an alien-human hybrid, it shouldn't be too hard. Since you're already using DNA, you're pretty much sticking to what humans have anyway. (Who knows what aliens would use to replicate? Probably not DNA anyway.) That makes it easy.

You can have your scientist talk about genetic markers, or specific genetic sequences that are common to humans but not aliens. You could mention, if you want, chromosomes. How many chromosomes do aliens have? Humans have 46 chromosomes in 23 pairs. Perhaps this alien has an extra chromosome? (Lots of people do, especially when it's sex chromosomes). That would be fairly easy to mention, and fairly safe, since it's not always fatal to have an extra chromosome. Or maybe it has too few chromosomes, that can happen too. The formal test for chromosomes is called a karyotype if you want to go in that direction.

Fenika
07-04-2007, 09:03 AM
And today's random reference goes to- Dawkins

http://www.amazon.com/Selfish-Gene-Richard-Dawkins/dp/0199291144/ref=pd_bbs_sr_3/103-7116219-4271025?ie=UTF8&s=books&qid=1183525100&sr=8-3

This might inspire you to come up with an idea, and it will help you understand genetics...

Perhaps the alien has some way to overcome the lack of relate-ness? It could have the genetic equivalent of a translator...

Okay, you didn't ask about how, but it's still neat stuff :)

Also-
Heck, while horses and donkeys cross nicely into mules, you can barely get a horse-zebra cross to work (but it does happen- the result is a zorse)

Selimthegrim
07-04-2007, 09:09 AM
That's a good point bahamut, and it brings up the question of whether or not the resulting human-alien hybrid would be sterile. Most cross-species hybrids end up being unable to reproduce themselves. But, I guess if the book isn't about human-alien pornography then there's not too much to worry about :tongue

Plot Device
07-04-2007, 04:26 PM
See my avatar.




Scully approves.

Eiko
07-05-2007, 11:26 AM
Well, a good starting point would be:
http://en.wikipedia.org/wiki/Genetics

And for the question of human/alien-crossbreeds perhaps of interest also:
http://exobiology.arc.nasa.gov/ssx/exobiology.html
http://exobiology.arc.nasa.gov/

And here's one more that's remotely connected to the difficulties that might arise when mating with aliens... ;-)
http://en.wikipedia.org/wiki/Carbon_chauvinism

triceretops
07-05-2007, 12:45 PM
Well, I forget who said it, but somebody said that it would be more likely that humans could mate with flowers than with aliens, because at least humans and flowers evolved on the same planet

Carl Sagan said that.

Tri

Selimthegrim
07-05-2007, 03:12 PM
Well, I forget who said it, but somebody said that it would be more likely that humans could mate with flowers than with aliens, because at least humans and flowers evolved on the same planet

Carl Sagan said that.

Tri

Thanks!

job
07-05-2007, 08:04 PM
One good take on human-alien interbreeding is in Card's Wyvern. It proposes an alien species that inserts a small replicating bit -- rather like a virus inserting itself. The presumption is this ability to hijack other species' germ lines extends across many forms of reproduction.

Good pseudoscience.

Julie Worth
07-05-2007, 08:17 PM
Well, I forget who said it, but somebody said that it would be more likely that humans could mate with flowers than with aliens, because at least humans and flowers evolved on the same planet.

This is true, but it's possible to insert working human genetic material in other species--eg, mice. So, it's not entirely unbelievable that the same could be done with aliens, assuming they happened to use the same DNA code.

Selimthegrim
07-05-2007, 10:13 PM
This is true, but it's possible to insert working human genetic material in other species--eg, mice. So, it's not entirely unbelievable that the same could be done with aliens, assuming they happened to use the same DNA code.

Well, assuming vastly superior technology to what we have now, then yes. It would just be so incredibly unlikely that alien and human genetic recombination could produce viable offspring as to be completely negligible. However, I'm sure that extremely advanced societies could use laboratory techniques to do what nature cannot.

job
07-06-2007, 12:11 AM
This is true, but it's possible to insert working human genetic material in other species--eg, mice. So, it's not entirely unbelievable that the same could be done with aliens, assuming they happened to use the same DNA code.


But y'see .... that's the point. They wouldn't use DNA.

Using the same chemicals I do for their alien reproduction method would be far less likely than aliens writing in the alphabet I'm using.

The whole concept .... it's like tossing half Japanese characters in and half English letters in and shaking them up and pouring out a usable computer program.
Somebody who knows programming languages is just going to hold his cranium in both hands, wondering how he can begin to explain why this wouldn't work.

Selimthegrim
07-06-2007, 12:23 AM
But y'see .... that's the point. They wouldn't use DNA.

Using the same chemicals I do for their alien reproduction method would be far less likely than aliens writing in the alphabet I'm using.

The whole concept .... it's like tossing half Japanese characters in and half English letters in and shaking them up and pouring out a usable computer program.
Somebody who knows programming languages is just going to hold his cranium in both hands, wondering how he can begin to explain why this wouldn't work.

I'm not entirely sure aliens wouldn't use DNA. Considering that early Earth conditions have been shown to spontaneously form basic amino acid chains, from which DNA could have developed, it's entirely possible that aliens on a planet with similar conditions to early Earth could have formed DNA as their method of replication as well. After all, there are only so many elements in the universe, and the laws of physics and chemistry would apply as much on their planet as ours. However, I agree that such a thing is probably highly unlikely.

waylander
07-06-2007, 12:28 AM
I'm not entirely sure aliens wouldn't use DNA. Considering that early Earth conditions have been shown to spontaneously form basic amino acid chains, from which DNA could have developed,

DNA does not contain amino acids

Julie Worth
07-06-2007, 12:31 AM
"The whole concept," Selim said, "it's like tossing half Japanese characters in and half English letters in and shaking them up and pouring out a usable computer program."

"But they're aliens," I protested. "They might be a million years ahead of us."

"Poppycock. Anyone who knows programming languages is just going to hold his cranium in both hands, wondering how he can begin to explain why this wouldn't work."

I held my tongue, even though I'd seen the creature myself--half woman, half ungodly beast from some other world. A scientist like Selim knew what was possible and what wasn't. He wouldn't believe his own eyes, so he sure wouldn't believe mine.

Selimthegrim
07-06-2007, 12:54 AM
"The whole concept," Selim said, "it's like tossing half Japanese characters in and half English letters in and shaking them up and pouring out a usable computer program."

"But they're aliens," I protested. "They might be a million years ahead of us."

"Poppycock. Anyone who knows programming languages is just going to hold his cranium in both hands, wondering how he can begin to explain why this wouldn't work."

I held my tongue, even though I'd seen the creature myself--half woman, half ungodly beast from some other world. A scientist like Selim knew what was possible and what wasn't. He wouldn't believe his own eyes, so he sure wouldn't believe mine.

I actually didn't say any of that. You've misquoted.

Selimthegrim
07-06-2007, 12:55 AM
DNA does not contain amino acids

You're right, I misspoke. But at any rate, the primordial soup of early Earth could be duplicated on countless worlds. I don't know if DNA is an "ideal" form for storing information and replicating it, but it might be a very common one.

veinglory
07-06-2007, 02:29 AM
I think it is unlikely that separately evolved aliens would have DNA. But there are theories that life is seeded on different planets by a common source (panspermia). All the same having an alien more like us than, say, a chimp would require some explanation IMHO.

job
07-06-2007, 03:54 AM
"The whole concept," Selim said, "it's like tossing half Japanese characters in and half English letters in and shaking them up and pouring out a usable computer program."

"But they're aliens," I protested. "They might be a million years ahead of us."

"Poppycock. Anyone who knows programming languages is just going to hold his cranium in both hands, wondering how he can begin to explain why this wouldn't work."

I held my tongue, even though I'd seen the creature myself--half woman, half ungodly beast from some other world. A scientist like Selim knew what was possible and what wasn't. He wouldn't believe his own eyes, so he sure wouldn't believe mine.


Oh, giggle.

job
07-06-2007, 04:23 AM
You're right, I misspoke. But at any rate, the primordial soup of early Earth could be duplicated on countless worlds. I don't know if DNA is an "ideal" form for storing information and replicating it, but it might be a very common one.


There's nothing special about nucleic acids.
Right off the top of my head I could name a couple radically different paths -- You could use silica compounds with flourine, for instance. Or benzenes. Some sugar compounds.

From the same primordial soup, there is nothing inevitable, or even likely, about the set of nucleic acids we use on earth.

Selimthegrim
07-06-2007, 04:32 AM
There's nothing special about nucleic acids.
Right off the top of my head I could name a couple radically different paths -- You could use silica compounds with flourine, for instance. Or benzenes. Some sugar compounds.

From the same primordial soup, there is nothing inevitable, or even likely, about the set of nucleic acids we use on earth.

Do those silica compounds or benzenes have the same properties of DNA - ease of replication, redundancy (each side of the molecule contains all of the information), etc? I don't have a lot of formal scientific training, but I'm curious to know a little more about alternate means to achieve the same end.

As to inevitability, I didn't mean to imply that. But given an infinite number of worlds and an infinite number of primordial soups, you'll get some overlaps I'm sure. So while I wouldn't advise half-human half-alien people in any scifi world where the sci matters a great deal, I think it's a stretch that can be made in a piece of entertaining fiction.

Peggy
07-06-2007, 04:47 AM
Even if your aliens used nucleic acids, the actual code might might be the same. Here on Earth AUG codes for the amino acid methionine. On planet Zorblax maybe it codes for glycine - or some amino acid not even found in humans. If you really want the aliens to use the same kind of DNA as Earthly life, you probably have to invoke some kind of panspermia in your universe.

http://en.wikipedia.org/wiki/Panspermia

Peggy
07-06-2007, 04:52 AM
So while I wouldn't advise half-human half-alien people in any scifi world where the sci matters a great deal, I think it's a stretch that can be made in a piece of entertaining fiction. Indeed, as Spock might say. You have to decide how true to science your fiction is going to be - and then just be sure it's consistent within the universe you create.

ErylRavenwell
07-06-2007, 09:03 AM
There's no such thing as "Human DNA". The repeating units of the DNA are the same for all Earth's living things, be it a bacteria or a human being. Human genome, yes; Human DNA, no.

DNA stands for deoxyribonucleic acid and is made of repeating units of nucleotides: Adenine, Guanine, Thymine, Uracil and Cytosine.

Now, in an alien species, which had evolved in an environment radically different than Earth's, it is possible that one or more nucleotides may be diffferent. This would be how you'll be certain the baby is alien. Then, if that were the case, consider it virtually impossible for a human and the alien of that species to conceive a baby naturally (a human and cow would have better odds at that). Alien-human baby hybrid is cliche and scientifically unsound. The key word here is "naturally" of course.

job
07-07-2007, 10:58 PM
Do those silica compounds or benzenes have the same properties of DNA - ease of replication, redundancy (each side of the molecule contains all of the information), etc?.

Well, yes. That's why I suggested them. I didn't just pick compounds out of the air.


I don't have a lot of formal scientific training, but I'm curious to know a little more about alternate means to achieve the same end.?.

(jo scratches head)
Ah ... putting it in a nutshell --
different chemicals can perform the same basic function of storing and transmitting information. Nucleic acids are not unique.

As to why there are other chemicals that work just as well and which ones they are and what the characteristics of such chemical systems would be ... I think you'd need some understanding of chemistry to get a good grasp of that.

It's like saying ... 'Windows was not inevitable. There are other ways to structure an operating system."
A systems analyst would say, 'Oh. Of course. Here's what you could do ..."

Me, I couldn't intelligently compare computer architectures. No training. Not willing to study for a year so I could understand them.



As to inevitability, I didn't mean to imply that. But given an infinite number of worlds and an infinite number of primordial soups, you'll get some overlaps I'm sure. ?.

The infinite numbers of chimps theory. Well. Yes.



So while I wouldn't advise half-human half-alien people in any scifi world where the sci matters a great deal, I think it's a stretch that can be made in a piece of entertaining fiction.

Wise, immortal dragons. Fairies at the bottom of my garden. Elves in velvet and lace.
I love them all.
It's fiction. Go wild. Write about it.
Call it 'parallel dimensions'. Call it 'magic'. Call it 'paranormal powers'.

Half-alien babies spawned by 'advanced alien technology' in 'hovering spaceships'.
Cool.

I have one answer for 'how do I handle this in fiction,'
and another answer for 'could this really happen.'

You might visit here (http://sciencefictionbiology.blogspot.com/2007_02_01_archive.html), which is 'Peggy's' blog on 'Biology in SF'.

Greenwolf103
09-17-2007, 08:44 PM
Well, yes. That's why I suggested them. I didn't just pick compounds out of the air.



(jo scratches head)
Ah ... putting it in a nutshell --
different chemicals can perform the same basic function of storing and transmitting information. Nucleic acids are not unique.

As to why there are other chemicals that work just as well and which ones they are and what the characteristics of such chemical systems would be ... I think you'd need some understanding of chemistry to get a good grasp of that.

It's like saying ... 'Windows was not inevitable. There are other ways to structure an operating system."
A systems analyst would say, 'Oh. Of course. Here's what you could do ..."

Me, I couldn't intelligently compare computer architectures. No training. Not willing to study for a year so I could understand them.




The infinite numbers of chimps theory. Well. Yes.




Wise, immortal dragons. Fairies at the bottom of my garden. Elves in velvet and lace.
I love them all.
It's fiction. Go wild. Write about it.


LOVE this.

Thanks, everyone, for ALL of your comments and suggestions. Just an FYI (and maybe I SHOULD have mentioned this, sorry): The alien/human hybrid baby is genetically modified. In other words, it came from a lab. In other words, it's all a secret that the creator didn't want anyone to find out. So, there's been some tampering with the standard alien biological make-up and genetic code which the scientist in my story is educated about.

Here is what I ended up writing. Please let me know if it sounds right:

“Something is wrong,” Fiona said, leading Altman into the lab. “My readouts aren’t consistent with Agent Pitt’s research and I’m picking up on things that aren’t supposed to be there.” She showed him a long stream of chart readings. “See? They’re supposed to have 24 chromosomes in 12 pairs, but it has 46 in 23 pairs. Adenine, Guanine, Thymine, Uracil and Cytosine. Just like us. And I’m picking up readings of carbon.” She caught Altman’s surprised look. “Carbon. Aliens aren’t carbon-based lifeforms, according to Pitt’s reports.”

And by the way, I recently saw the movie DOOM and how a human with extra chromosomes turned into a "superhuman" or...monster. Food for thought on how it affects the alien race, which is really something that can be practically anything in the fictional world....

GeorgeK
09-18-2007, 07:32 AM
I think it is unlikely that separately evolved aliens would have DNA. But there are theories that life is seeded on different planets by a common source (panspermia). All the same having an alien more like us than, say, a chimp would require some explanation IMHO.

Like humans are already hybrids of aliens and chimps from an experiment 400,000 years ago and so this character is 3/4 rather than 1/2 alien? they came back to finish the job because a change in politics has made the Earth, no longer "off limits"? Or maybe the daddy is a rogue alien conducting his own prurient interests...I mean scientific experiments?

The nice thing about sci-fi is that unexplainables can be ok, and btw, Carl Sagan was not God. (Ignore it, it's a pet peeve) The thing I would object to most about DNA comparisons is that it takes months to sometimes years to get the data back and so is horribly overused in crime stories. The CSI shows must have tricorders. If you want something the FBI lady can readily identify as non human, then give it an extra organ, or cartilaginous rather than bony skeleton, or gills, but not pointed ears, anything but that.

GeorgeK
09-18-2007, 07:47 AM
LOVE this.


Here is what I ended up writing. Please let me know if it sounds right:

“Something is wrong,” Fiona said, leading Altman into the lab. “My readouts aren’t consistent with Agent Pitt’s research and I’m picking up on things that aren’t supposed to be there.” She showed him a long stream of chart readings. “See? They’re supposed to have 24 chromosomes in 12 pairs, but it has 46 in 23 pairs. Adenine, Guanine, Thymine, Uracil and Cytosine. Just like us. And I’m picking up readings of carbon.” She caught Altman’s surprised look. “Carbon. Aliens aren’t carbon-based lifeforms, according to Pitt’s reports.”

And by the way, I recently saw the movie DOOM and how a human with extra chromosomes turned into a "superhuman" or...monster. Food for thought on how it affects the alien race, which is really something that can be practically anything in the fictional world....


Med school was a long time ago, but if I remember correctly Uracil is in RNA rather than DNA...if that matters to you? There's no reason to say your scientists couldn't be studying both, or maybe had contaminated samples. Also are you saying that in your MS there already exists a text about aliens stating that they are not supposed to be carbon based and that they are not supposed to have 46 chromosomes? To be fair, there is more myth than science about what and how all the DNA does stuff anyway. In undergrad they misrepresent a lot of stuff to sound like they know more than they do. In doctoral and post doc sciences you find out how little is actual truth and how so much is theory, so do whatever you want.