GCTGGTGG

GCTGGTGG is an eight-nucleotide DNA sequence (an octamer) written in the 5' to 3' direction as GCTGGTGG. As a short oligomer, it has no inherent biological function by itself; its significance depends on genomic context or experimental design.

Composition and properties: The sequence comprises five guanine (G) residues, one cytosine (C), and two thymine (T) residues, with no adenine (A). This results in a GC content of 75%, and a predicted high duplex stability for short oligonucleotides. The lack of adenine reduces propensity for certain kinds of mispairings, but its high GC content can contribute to higher melting temperatures compared with more AT-rich 8-mers. In isolation, it is unlikely to form stable intramolecular secondary structures such as hairpins.

Biological and experimental contexts: In real genomes, the function of an eight-base motif is determined by location; the sequence could appear within coding regions, promoters, or noncoding regions. As a standalone motif, GCTGGTGG does not specify a known regulatory element or recognition site for widely used restriction enzymes. In laboratory practice, octamer sequences are used as short DNA barcodes or as components of larger oligonucleotides in assays, though 8-mers alone are typically too short to serve as primers for polymerase chain reaction.

Computational use: In bioinformatics, short k-mers such as this eight-base sequence are used to profile genome composition, study sequence complexity, or assist in assembly and error-checking. The frequency of this specific octamer will vary with organism GC content and genomic context.