A gene is a region of DNA that encodes proteins and regulatory elements that determine the characteristics of a lifeform. Genes are organized into macromolecular structures called chromosomes.
Lyris referred to Harry Kim's Taresian genes while trying to convince him that he was conceived on Taresia. (VOY: "Favorite Son")
The Doctor informed Neelix that his change in appearance was the result of stimulation of the Mylean genes he inherited from his great-grandfather. (VOY: "Scientific Method")
The gene for sensory tremens was suppressed in Chakotay before he was born, but was reactivated by an encounter with chaotic space. (VOY: "The Fight")
Captain Janeway jokingly asked Mortimer Harren if he was missing a couple of base pairs from gene 178 while on an away mission in the Delta Flyer. (VOY: "Good Shepherd")
The Doctor and B'Elanna Torres discussed deletion of genes from her unborn child. (VOY: "Lineage")