SECIS elements are thus a fundamental aspect of messenger RNAs encoding selenoproteins, proteins that include one or more selenocysteine residues.

In bacteria the SECIS element appears soon after the UGA codon it affects.

The eukaryotic SECIS element includes non-canonical A-G base pairs, which are uncommon in nature, but are critically important for correct SECIS element function.

[4] In bioinformatics, several computer programs have been created that search for SECIS elements within a genome sequence, based on the sequence and secondary structure characteristics of SECIS elements.

[5] The SECIS element is found in a wide variety of organisms from all three domains of life (including their viruses).