The Corona viruses I know of are mostly GI. I wonder if chicken or turkey Chlamydia has adapted to human hosts - lots of stories of how mainland tenant farmers keep poultry in their houses.
As the weeks pass i am sure other links and theories will pop up. Until then your guess is as good as mine.
As for it being G1 (i believe you are referring to group 1) i am not sure, but probably in my opinion would be together with Influenza (that i believe ....i might be wrong ....is a G2 pathogen. Ebola,Marburg and other haemorrhagic viruses, by comparison, are group 4 pathogens).
SARS is not as bad as Ebola obviously, but it is able to spread quite fast. The terror of scientists is a virus with the potency of Ebola (an exceedingly high deathrate which comes in an extremely graphic manner ....think bleeding from every pore and orifice in your body) that also has the infection-spread capability of the Flu, and does not kill extremely fast!
The last point is important because the great thing about Ebola is that it is a very fast killer! It is so deadly that all who are infected die so quickly that the virus does not spread far beyond its locality! Now imagine if there was a virus with the lethal potency of Ebola, could spread through droplet ...or even worse was totally airborne .......and did not kill its host too quickly, allowing it to spread more efficiently!
With global transport and a small world the whole thing could hit every major metropolitan area long before the CDC, and its counterparts, smelt anything rotten! And if it had the lethality of Ebola (the most virulent strain is over 90% lethal ....and there is no cure, obviously LOL) then we would be looking at a death toll that is basically straight out of the book of Revelations in the Bible.
Estimates show that the human race would probably face its greatest threat ever! Not all would die ....but some models have shown that the deathtoll would be immense ....in the billions (especially if you factor in secondary diseases .....for example the mass of bodies, that would obviously not be buried, would lead to things like Cholera, dysentry, and other nasties that are really nto nice ........and then the smell!)
Now, SARS is nothing compared to that extreme! Not even close. But the scary thing about SARS is something scientists have been saying for decades! That as the world continues becoming smaller and travelling is fast then ailments that were previously trapped in some Asian swamp or brazilian jungle would be released into the whole world! The emrgence of AIDS, ebola, Marburg, and now SARS (if you read the 'Hot Zone' they have a list of viruses that have emerged from the forests of Africa, Asia and S. America that is very long). It is just a matter of time, i guess, before something that is really nasty comes out.
And that is why SARS bothers me ....because it shows new stuff is still coming out. SARS by itself is not that horrible ......although it has seriosuly hit the Hong Kong Hang Seng index and affected various socio-economic factors there. It is bad ....but it is not an air-borne hemorrhagic fever virus!
My personal nightmare is this: Ebola Zarie is the most virulent Ebola strain .....well over 90% fatality (small pox does not even come close to that). And 90% is even if you are in the best medical facility in the world! And you bleed from all your orifices, you sweat blood, your eyes turn black and red, you vomit up your intestines as it sloughs off (it is called black vomit), your internal organs start to liquefy, and all this happens while you are still alive!
Now, think of Ebola Zaire ....and then move on to Ebola Reston!
Ebola Reston is an ebola strain (instead of Africa this one came from the Asian jungles). The good thing is that it only affects monkeys, hence humans are safe. The bad thing .....and this is very bad .....is that ebola Reston is airborne! Not just heavy droplet but airborne. Meaning someone does not have to cough sputum at your face but simply be in your proximity!
Now picture this! There are several strains of Ebola. The most virulent human strain is E. zaire. Then i believe E. Sudan is a close second. None of them are airborne. The other hemorrhagic fevers afflicting humans, like Marburg (which is also pretty nasty) are also not airborne.
E. Reston is fully airborne ....but it snacks on monkeys and hence we are safe from it.
What if, and this is not such a big if, there was an Ebola strain that targeted humans AND was airborne? What if lurking in the Guatemalan jungle, or an african cave, or an asian mangrove swamp was such a virus?
Or what if your 'everyday' E.Zaire mutated and became airborne? Viruses mutate a lot ....actually the big problem with all viruses when it comes to their treatment is that they can mutate so easily by making minute changes to their protein coat that effective medicine is really not possible. That is why there are no medicines that can cure the flu, the common cold, HIV, Ebola! Hence what if E.Zaire suddenly, by some twist of fate, made a slight adjustment in its protein coat that made it airborne?
Obviously this is speculation on my part ......but ask the CDC and they can tell you what i described is EXACTLY what they most fear. And there is nothing they can do about it.
As we stand it is basically hoping there is no such virus out there ......and if there is then that it never makes it out of whatever jungle or cave it resides in.