LONDON (Reuters) - Crypto company Tether has invested $200 million in Blackrock Neurotech, taking a majority stake in the U.S. brain implant company, Tether said in a statement on Monday.

Blackrock Neurotech makes brain-to-computer interfaces, including neural implants which can allow people to control computers and prosthetic arms without moving, its website says. It has no relation to the asset manager BlackRock.

The deal, which closed on Friday after several months of due diligence, values Blackrock Neurotech at around $350 million, making Tether its largest shareholder, Tether CEO Paolo Ardoino told Reuters.

The $200 million from Tether will primarily fund the commercialization and roll-out of Blackrock Neurotech's technology, which has been used with more than 40 individuals, Tether's statement said.

In recent years, various device companies, including Elon Musk's Neuralink, have begun testing brain implants in humans.

Tether issues a dollar-pegged cryptocurrency which has grown rapidly in recent years, hitting $100 billion in circulation in March. It says that the tokens are backed up by dollar-denominated reserves.

Tether has made approximately $1.7 billion in venture capital investments to date, using funding from its profits, while leaving the reserves untouched, Ardoino said.

Tether invests in sectors including sustainable energy, artificial intelligence and peer-to-peer technology, its website says. The arm which invested in Blackrock Neurotech is called "Tether Evo", and is "dedicated to propelling humanity into a future where technology and human capabilities merge in unprecedented ways" the website says.

Blackrock Neurotech did not immediately respond to Reuters questions about the deal.