5 men arrested over sales of genetically modified killifish

Tokyo police on March 8 arrested five men on suspicion of illegally breeding and selling killifish that were genetically modified to make them “red and shiny.”

Genetically modified organisms can devastate existing creatures in the wild by taking over their food supplies and habitats.

To protect ecological systems, a law took effect in Japan in 2004 that spells out the rules on the safe handling of genetically modified organisms.

The five suspects, ranging in age from 60 to 72, are the first people accused of violating the law.

One of the suspects is Tomio Masuda, a 67-year-old resident of Kasukabe, Saitama Prefecture, who owns a store that sells killifish.

According to police, the arrested aquarium fish enthusiasts have admitted to the allegations, saying they “wanted to get the killifish because they were beautiful like never-seen-before.”

The fish were hatched from the eggs of genetically modified killifish bred at a research center of the Tokyo Institute of Technology in Yokohama. A male student stole the eggs in 2009, police said.

The killifish turned red because of the gene modifications.

The science ministry on March 8 issued a severe reprimand to the university for its inappropriate handling of killifish.

According to police, the five men bred minami-medaka killifish from the eggs, and then transported the fish with the intent to sell from July 2021 until August 2022.

The men sold the fish at trade shows or in private markets without disclosing the fact that the fish were genetically modified.

The fish were billed as “rare and shiny killifish.” Their prices ranged from 150 yen ($1.10) for one to 100,000 yen for a pair.

Police believe that the men distributed such killifish to around 50 people. Investigators have seized about 1,400 killifish from related locations.

The statute of limitations has already expired in the egg-theft case of the student, who is now 35 years old.

The ecology-protection legislation is called the Law on the Conservation and Sustainable Use of Biological Diversity through Regulations on the Use of Living Modified Organisms.

The law is also known as the Cartagena law, named after the city in Colombia where an international conference was held to discuss related measures.