The gamma-linolenic acid molecule

The γ- (gamma-) linolenic acid molecule - rotatable in 3 dimensions

γ- (gamma-) linolenic acid (GLA) is an omega-6 (omega minus six) fatty acid .

This means that it has a double bond between carbon atoms starting at the Ω (omega) - 6 position, which is 6 carbons back from the end opposite to the -COOH group (which is normally counted as the α (alpha) carbon - number 1).

It has 3 double bonds. Each of these double bonds is in the cis form, rather than the trans form, so the single hydrogen atoms are on the same side of the bond. Alternative names for the molecule are (6Z,9Z,12Z)-octadeca-6,9,12-trienoic acid, all-cis-6,9,12-octadecatrienoic acid or 18:3(n-6).

It is especially common in evening primrose (Oenothera) oil.

Alpha-linolenic acid is another isomer of this compound, with different properties.