A spokesperson at the California consumer agency said it could not confirm the existence of the investigation or comment on what specific charges have been leveled against Zayner, whose piercings and spiky hair have made him instantly recognizable.

Biohacking, or DIY biology, typically refers to people who carry out simple experiments outside of university labs and companies. But some biohackers have taken things one step further, injecting or swallowing various types of home-brew gene-therapy treatments.

Zayner, who posted a copy of the letter to his Instagram account, says he believes he is being unfairly persecuted for “genetic self-experimentation and showing people how to access publicly available knowledge.” He also denied providing medical treatment to anyone.

“I have never given anyone anything to inject or use, never sold any material meant to treat a disease and never claim to provide treatments or cures because I knew this day would come,” Zayner wrote.

Anyone can file a complaint with California’s medical board, but the existence of an investigation would mean the charges are considered credible. Practicing medicine without a license can be a misdemeanor or a felony in California, with penalties of up to three years in jail and a $10,000 fine.

www.instagram.com/jzayner/

Zayner declined to comment, saying he did not believe MIT Technology Review would portray him in a positive light.

In YouTube appearances and elsewhere, Zayner often makes the case that the government is blocking cures, employing hashtags such as #RightToTry, #RightToLive, and #BodyAutonomy.

“People are dying” because the US government “refuses to allow people access to cutting edge treatments or in some cases even basic healthcare,” he posted. “Yet I am the one threatened with jail.”

So far, biohackers have not yet developed any notable genetic treatments. And their experiments are sometimes carried out in a reckless, circus-like atmosphere unlikely to produce anything useful. Zayner himself has said “there’s no doubt in my mind that somebody is going to end up hurt eventually” as biohackers seek fame through self-experimentation.

Zayner’s rebellious rhetoric is part of his business model of winning attention for what he says is a profitable business, The Odin, which he operates out of a garage and which sells a variety of DIY biology kits, including a $209 kit for making fluorescent yeast.