How Did the Hulk Become the Hulk? Science Finally Speaks.

In a fun set of videos released this week, the Stanford postdoctoral research fellow explained the science behind the two superheroes’ origin stories.

He speculated that creating Captain America would require the use of emerging genome-editing tools like zinc finger nucleases or CRISPR/Cas9 systems, which allow researchers to effectively cut and paste bits of DNA.

That could theoretically allow scientists to “turn on genes that make your muscles physically large, make you strategically minded, incredibly fast, or increase your stamina,” Alvarado said.

But don’t cancel your gym membership just yet.

While these are powerful tools that have demonstrated some promising results to date, researchers are just beginning to explore their potential for treating disease. Superpowers will have to get in line.

As for the Incredible Hulk, Alvarado theorizes that when Bruce Banner’s DNA reassembled after that gamma radiation blast, it did so sloppily, inadvertently inserting a series of “epigenetic switches” that would turn certain genes on or off based on external factors. Specifically, of course, whether or not you’re foolish enough to make him angry.

But Alvarado acknowledged there are some questions even science can’t answer, like: Why do the Hulk’s pants always stay on?

See the videos below:

This article originally appeared on Recode.net.