eRNA is short for efference RNA, a kind of nucleic acid that does not code for proteins, but seems to perform crucial functions in the regulation of gene expression.

Reference: Mattick and Gagen, Molec. Biol. Evol. 18 : 1611-1630,2001

---

In Norse mythology, Erna was the mother of eleven sons by Jarl, the ancestors of the race of warriors in Norse society. Her father was Hersir, a tribal chief.

---

Erna also refers to the fictional world created by C. S. Friedman in her novels Black Sun Rising , When True Night Falls , and Crown of Shadows , which collectively make up The Coldfire Trilogy .

---