Figure 5: Structures of some ω6 polyunsaturated fatty acids present in marine samples. Hexadecadienoic acid (16:2ω6), linoleic acid (LA, 18:2ω6), -linolenic acid (GLA, 18:3ω6), arachidonic acid (ARA, 20:4ω6), and ω6 docosapentaenoic acid (ω6DPA, 22:5ω6) are all related biochemically because of the location of the first double bond 6 carbons from the methyl end of the chain.