OK, I brushed up on my Trek history and this is the bio I came up with...
Andy Tigan is the younger cousin of Captain Ezri Dax (USS Aventine) and was recently accepted by the Trill Symbiote Commission to be the 9th host of the Perim symbiote; a lifeform that has lived since the 20th Century and was most recently joined with Kell Perim (Conn officer on the USS Enterprise-E)
Andy was born on Xenex and fought alongside M'k'n'zy Calhoun in the Danteri Revolution, eventually joining Starfleet and working on the Luna-class Starship Development Project.
Andy now holds the rank of Captain and is resolved to finding a diplomatic solution to the current Klingon/Gorn crisis.
I chose a female character as I'd rather spend my time staring at a woman's butt than a bloke's