J - J'naii
The J'naii are a genderless, androgynous race. However, occasionally, individuals are born who have urges for maleness or femaleness. This is considered a form of sickness by their government. Any individual suspected of having such gender identity can be taken into custody and a psychotectic therapy is used to change their gender identity to androgyny.
This resulted in a subculture forming inside J'naii society where the gender-oriented individuals search each other out in secret, to express themselves and their love for each other through the gender roles. This minority always lives in fear of being discovered. x
The J'naii appear in TNG “The Outcast”, where female identifying Soren and commander Riker fall in love. Jonathan Frakes would later criticize the decision to cast women in the roles of the J'naii, as a love affair shared between two men would have made the statement of the episode stronger. x