I'm trying to figure out the name of a movie I saw on TV as a kid, in the mid-to-late 90s. I remember it being kind of Starship Troopers-esque, but everyone had these glowing lights in their chests. They glowed in different colored patterns, and I think it had something to do with whether you were attracted to someone or not (I was probably like 7 when I saw it, I didn't really understand the context of that part yet).
If it's the one I'm thinking of, it was a pilot for a series that never aired called "Island City". Does this sound familiar?
In the future, humanity develops a "fountain of youth" drug, but as many people around the world begin to take it, most begin to mutate into a barbaric proto-humanoid state. The few people immune to this side-effect of the drug band together and live in a futuristic city while the mutants live in the vast wasteland outside its gates.
Citizens of the city wore a colored crystal on their sternum and could only mate with other citizens of the same color, which was based on the individual's genetic makeup. Progeny that resulted from breeding outside of your prescribed color would have the genetic mutation that, when combined with the "fountain of youth" drug, created the race of proto-humanoids.
Thanks to the wonders of Youtube, here's the intro. In some of the scenes, their uniforms are unbuttoned just enough that you can see the crystals embedded in the chest.
The show had some popular 90's actors in it but never took off. I didn't realize until I looked just now, but the main character was played by Kevin Conroy, widely famous as the voice of Batman.
The episode Legacy of Star Trek: The Next Generation featured a planet full of underground tunnels and rag-tag warriors who had proximity sensors in their chests that caused them to glow in kind of a blinking way. Could that be what you're thinking of?
You can see a YouTube video that shows the glowing chest effect below, at the 3-minute mark.
In the movie Cocoon during a swimming pool scene didn't they glow when the aliens wanted to "share" themselves. I can't exactly remember if it was just there chests or the whole body though. I found a link in youtube but don't know how to link it here.
Laserblast (1978), but played on TV when you asked.