Under the Dome features a lesbian couple, Carolyn and Alice, who are portrayed as a normal, loving family unit. While Alice tragically dies, her death is a consequence of the dome's dangers, not her identity. The show normalizes their relationship, treating it with dignity and respect, thus providing a net positive portrayal.

The character Dodee Weaver, originally white in the novel, is portrayed by an Asian-American actress. Similarly, Carolyn Hill, also white in the source material, is played by a Black actress in the show.

The show predominantly portrays Christianity through figures like Reverend Coggins and Big Jim Rennie, who are depicted as deeply corrupt, hypocritical, and manipulative. They exploit religious rhetoric and institutions for personal power and control, with the narrative consistently exposing their immorality and the destructive consequences of their actions.