An obelisk is a microscopic genetic element that consists of a type of infectious agent composed of RNA.
Described as a "viroid-like element", they consist of RNA in a circular rod shape without any protein shell coating.
The authors of the January preprint named these sequences "obelisks" due to a predicted rod-like secondary structure: "At 1164 nt [nucleotides] in length, the rod-like secondary structure was striking [...]"[3] Viroids were known to exist in plants and cause pathology, and there had been no evidence that they were in animals or bacteria.
[3][7] The effect of obelisks on human health, if any, is yet to be determined,[4] as are issues such as their life cycles, and what factors their replication depend on.
In contrast to viroids, their RNA is translated into proteins, tentatively called "oblins" in the preprint.