Is human hibernation possible?

The concept of human hibernation or the longer-term storage of humans by way of cryogenics has long thought to be the Holy Grail for long-term space flight. There have been a number of Sci Fi movies using these concepts within their movie plots, sometimes it makes up most of the movie, thus, one could call it a sub-genre in the Science Fiction venue. Okay so, let's talk about this shall we?

Not long ago, a college student from the UK asked me a very interesting question after reading my writing on this topic; "Do you think that human hibernation is really possible? Well, consider this, it is known that hydrogen sulfide gas slows down the human bio-system to a near standstill. There are other ways of hibernating humans using various organic substances, and some less-than-favorable concepts, that might hold future innovations in hibernation.

You see, also with simple DNA Manipulation we should be able to create humans or other primates which can hibernate for very long periods of time. Bears and other species which have similar DNA could be used as the model. It is probable that during ice-ages humans and other primates did have the ability to hibernate for long periods of time, and survived living underground with little if any food supply.

We see many species which can do this, or buried eggs which spring to life with new water, just as doormat seeds can. It would be less-likely that past period humans didn't hibernate than, if they did, so most likely they did, and that same ability has components already available. If in the presence of compounds such as hydrogen sulfide gas, we may find that humans easily slip into hibernation and recover without hardly any repercussions.

There have been many instances of people reported deceased that spontaneously spring to life, and their bodies have gone into a hibernation-like state, then there are all the Comatose cases as well, and folks who have been frozen to death and revived. It's probably a lot more common in other species than for humans, but that's only because humans have grown to control their environment, and have perhaps lost the ability or it has been hidden from them. Now then, let me give you a really interesting side-bar hypothetical, as Russian Scientists are right now drilling into an old lake under the ice which has not been explored in 10s of thousands if not 100s of thousands of years.

What if there are frozen predecessors to humans down there, or what if there are frozen human-like genetic ancestors down there which we might bring back to life? Should we, and if so, then what? Please consider all this and think on it.