L-S VI was a planet located about six light years from the Gamma Quadrant aperture of the Bajoran wormhole.
In 2370, Doctor Mora Pol of the Bajoran Institute of Science mounted an expedition with Starfleet assistance to L-S VI, where probes had discovered DNA similar to Odo's. Silicate-based lifeforms were found on the planet, including a small vegetative organism with Changeling-like metamorphic properties.
During the expedition, Jadzia Dax, Mora Pol, and Weld Ram were injured from inhaling a ground eruption of volcanic gas. Odo was also unknowingly affected by the gas, which caused him to change into a large, instinct-driven creature back aboard Deep Space 9. (DS9: "The Alternate")
The ruins found on L-S VI are similar to the structures on the Founders' homeworld in DS9: "The Search, Part II", suggesting that Founders at one point may have had a presence on this world, before their retreat ten millenia ago. (citation needed • edit)