Writing about this is a bit of candy for me! I have read a number of books with the idea that 'aliens tinker with one or more species on a planet' and then leave. Some thousands of years later, the sentient inhabitants figure out what happened.

As blarman mentioned, this is part of the backsrory for the Lensman series; it also figures in Brust's Jereg series and SM Stirling's pastiches on Burroughs Venus and Mars books.

Dwarfism. there are two kinds ateliotic and achondoplastic. I tried to do a paper on the latter during college to see if there were a geographic cluster of where achondoplastic dwarves might have originated - but there was little data as to birth records. (I spent a lot of time in the stacks.) Boxers and bulldogs are both dwarf species of a mastiff-type progenitor. African pygmies are ateliotic (ie proportional, but undersized).

Immortality. If you postulate a sophisticated technological culture, you need to choose your abnormalities carefully. We know why Downs occurs - and there is no relation to aging that I know of. Immortality might be related to a mutation that resulted in an increase in cancer (telomerase activity), or to the premature aging syndromes that occur but probably not to albinism (which would increase Vit D uptake; Vit D is an antagonist to telomerase).

If you are hesitant to trigger PC backlash, you might want to put the action on another planet, possibly with another humanoid (hence sympathetic) species or with and offshoot of the human species transplanted there for experimentation.

There is a lot more tolerance for this sort of story in the SF world...the problems lie in mainstreaming the book, if that is your intention.

Jan, apologizes for misspellings - no time to proof

I have one for you: Prostate Cancer! This disease will kill all males as they age. To me, this shouldn't be and when you have a family history it's scarier yet! If your born a male you already have a death sentence given enough time.

I'm intrigued!

I say...let the public determine the success of your story. "Mean-hearted" has been used so many times by the Liberals that I generally ignore the term. Even if your fictional story was based upon fact, someone would find a way to twist the truth to show it never actually happened (like making the Holocaust disappear).

It's a very very very very very fictional sounding story. Not sure I'd run with it myself, kinda close to home for a lot of people.

first tell us about this past culture existed. if they did not exist then the things noted couldn't have been a result of tinkering.

Definitely interesting. Nature has done her fair share of genetic tinkering across the entire spectrum of living things, including some screw-ups that eventually vanish.

Today's human abnormalities result from less than successful mutations while we relatively normal humans are the result of successful mutations from times past. It would be nice if you could have your tinkerers fix those defects prenatally. Some such work is being done already.

It would be fun to introduce a subplot of deliberate engineering by ancient scientists or even visiting aliens. In fact, I'm toying with a story myself where the entire human race and its predecessors evolved from an organism with genetically modified DNA that would eventually lead to human evolution.

Your fictional engineers were partially successful with jellyfish, who do seem to have immortal cell replacement features. Now if that could only be applied to human brains, both hardware and software. One can dream...

Write on! In science fiction anything goes. Forget about the political objections du jour.

I find it quite interesting and along the lines of E.E. "Doc" Savage's Lensman series.

I'd say go for it.

I would call it interesting. I would want to carry it forward, not just genetically but socially.

Interesting. Through out the ages there are tales of superior races. The most notable for most is David and Goliath. So with that thought your thinking does hold merit. There are more cases but I would need more time to research accurate details.

There's been a number of science fiction books and movies made about such genetic tinkering in the wrong hands.
End result? Usually murdering monsters.
As for reality, Adolf Hitler had a thing for a genetically controlled race of Teutonic blonds that did not reach full fruition.
More murdering monsters.
What's becoming of the USA (along with science)?
I've seen more than one science fiction monster movie end with the following--
The End?

I certainly don't think it would be callused, and I also don't think it would be callous! You used both spellings, so I searched the universe for meaning...

[Calloused or Callused?
By Maeve Maddox

In its literal sense the adjective callous is used to describe parts of the skin that are hardened by constant friction or pressure. Used figuratively it refers to insensitive behavior, or hardness of the mind.

A variant spelling of callous is callus. This spelling is usually seen in connection with body parts:

Used literally, the spellings are interchangeable. A foot may be either calloused or callused.

When using the adjective in a figurative sense, however, stick to callous and its forms: a callous person, calloused behavior.]

If your work is fiction then I don't see how anyone could find it offensive unless you work hard to reach an offensive conclusion!

Interesting!

Sounds like a very interesting book or future movie. I see much leeway to develop a really awesome story line! Maybe like following the lineage of a single family or two!

What if it were an ongoing experiment searching for the genetic leap that would save their culture, and they progress check occasionally? It wouldn't be unusual to have 9 of 10 experiments go awry. What if the 1 of 10 or even 1 of 100 turned out to be Stephan Hawking or Steve Jobs, or Vanderbilt or Carnegie from a prior generation, and that distant culture hoped to take the genetic material from the successes back home?

As an author it's up to you whether your them is mean spirited or Devine.

Any story can be a best seller, provided you have a good plot, can write in such a way as to generate feelings for your characters, and keep people guessing.

One of my favorite movies. "What About Bob."

At first you feel bad for Bob (Bill Murray), and hate the arrogant Doctor, (Richard Dreyfus).

By the end of the movie you end up feeling so bad for the guy you dislike, and just hope Bob would foll all a cliff, in the end you end up liking both characters with all their flaws. The writers did a great job of switching the antagonist and protagonist back and forth just through the situational interactions.

I would certainly give it a read..Just don't refuse to serve a wedding cake to a gay couple ... LOL