Cognomen Gernia (Gernia 
) , in the entire world, is a very rare last name. The cognomen Gernia is habitual in Italy, where it is a very rare surname, and Mexico, where it is an extremely rare surname. Much more prevalently, Gernia is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Gernia | Italy, Philippines, Mexico, United States, Democratic Republic of the Congo |