What is a movable gene "Steamer" that causes "infecting cancer"?

Cancer infected from one individual to another has been found in some animals such as dogs and Tasmanian devils, but confirmed that cancers spread by infection as well in shellfish as well. In this shellfish, the mobile gene "Steamer"Factors called" have been found, and it is urgent to clarify the route of infection.

Activation of transcription and retrotransposition of a novel retroelement, Steamer, in neoplastic hemocytes of the mollusk Mya arenaria
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4191779/

This Jumping Gene Spreads Through Marine Animals' DNA - The Atlantic
https://www.theatlantic.com/science/archive/2018/04/the-shellfish-gene/558131/

In the late 1970s, it was confirmed that a great dead bird was dying on the coast of Maine State, USA. It was thought that leukemia was caused by cancerous cells found in the blood of the morning glory and milky discolored blood was packed in the organ and died, but the researchers could not find out the cause of the cancer.

About 40 years after the discovery of a mysterious leukemia, Dr. Stefan GOFT of Columbia University, Dr. Okinawa's leukemiaRetrotransposonIt is a cancer that is infected by. Dr. Gofo named a movable gene related to cancer as "Steamer". A healthy snail has 2 to 10 copies of Steamer in the DNA. However, 150 to 300 copies have been confirmed in the Earth snake who developed cancer.

Dr. Golf's research team looked at shells of the East Coast of the United States and found a gene like Steamer (Steamer like gene) also in shellfish DNA such as oysters, mussels and cockles. Strangely, some of these genes were surprisingly similar even though the host species, shellfish, were different. Specifically, although the genus identity was only 65% ​​as evidenced by the evolution of shellfish and mategar over 300 to 500 million years to different species of shellfish, about 97% of the Steamer gene was identical That's right.


Steamer has the possibility of cancer infection beyond the type of shells, but there are other Steamer like genes found in other organisms such as coral, sea urchin and fish. And Steamer - like gene found in zebrafish was almost the same as Steamer which was first discovered in Ogonogai.

It is not well understood about the pathway through which Steamer-like genes are infected among different organisms, but because they are moving between aquatic organisms, the possibility of infection in the water and marine parasites become carriers and make Steamer The possibility of carrying is considered.