Golden rice is an example of a GMO that's actually beneficial to humanity, or would be; anti-GMO sentiment has kept it from being grown in any significant amounts.

It's tweaked to produce vitamin A, which rice normally does not; deficiency is a common problem in places where the poor get most of their calories from rice

Nothing really it's a GMO that was created to fill a vitamin deficiency in some parts of Asia. Can't remember what vitamin it was though, absolutely brilliant success of a crop though. Funny enough some of the research on it may have used my 2x great grandfathers work as a baseline since he was working with some folks to do something vaguely similar with millet back in the early 1900s. It went nowhere but did lead to some success for his orange groves though.