A couple operating a fish shop in Tokyo have been arrested for allegedly cultivating without government approval a popular tropical fish genetically modified to glow, police said Wednesday.

The police arrested Hidehiko Takeda, the 66-year-old owner of the fish shop, and his 56-year-old Thai wife Somphorn, who runs the shop, for alleged violation of the Cartagena law, which came into force in 2004 to regulate the use of genetically modified living organisms.

The suspects sold the genetically modified Siamese fighting fish, or betta, as "neon betta" at the store, the police said. The fish glows in a yellow-green color when exposed to ultraviolet light.

Photo taken in Tokyo on Jan. 17, 2024, shows Siamese fighting fish, commonly known as betta, genetically modified to glow light green. The fish were confiscated by Tokyo police over an alleged violation of the Cartagena law, which regulates the use of genetically modified living organisms. (Kyodo) ==Kyodo

The couple allegedly cultivated 10 such fish in June at the shop without authorization after importing them from Thailand in May, police said.

The two have admitted to the allegations, with police quoting Takeda as telling them, "I have cultivated a genetically modified organism for sale."

In a related move, Tokyo police on the same day referred to prosecutors five people in their 50s to 70s for allegedly purchasing the glowing betta for 2,500 yen ($17) to 30,000 yen a fish, as well as the shop's operator, Azuma Keikaku, which Takeda heads, they said.

The arrests came after a 53-year-old man in Toyonaka, Osaka Prefecture, who was among the five referred to the prosecutors, exhibited the betta fish he had purchased at a domestic "beauty" contest for the fish in June last year. The contest organizer notified the Environment Ministry, which provided information to the police.

The Cartagena law requires parties seeking to keep and sell modified living organisms to obtain government authorization after proving the organisms will not negatively affect biodiversity. The law is based on the Cartagena Protocol on Biosafety to the Convention on Biological Diversity.

The police said they have so far not confirmed any impact on biodiversity, such as by disposing of the fish in the wild.

In March last year, police arrested a number of fish enthusiasts for their alleged involvement in the unauthorized cultivation of Japanese killifish genetically modified to glow in red.


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