Steer CD, Hibbeln JR, Golding J, Smith GD (2011) Hum Mol Genet. 2011 Dec 21.
Minor alleles of polymorphisms in the FADS gene cluster have been associated with reduced desaturation of the precursor polyunsaturated fatty acids in small studies. The effects of these polymorphisms during progressive developmental stages have not been previously reported.
Data from blood samples for 4342 pregnant women, 3343 umbilical cords reflecting the newborn's blood supply and 5240 children aged 7 years were analysed to investigate the associations of polyunsaturated fatty acids with rs1535 and rs174575 - two polymorphisms in the FADS2 gene.
Strong positive associations were observed between the minor G allele for these two markers, especially rs1535, and the substrates linoleic (18:2n-6) and α-linolenic (18:3n-3) acid. Negative associations were observed for the more highly unsaturated fatty acids such as arachidonic acid (AA, 20:4n-6), timnodonic acid (EPA, 20:5n-3) and cervonic acid (DHA, 22:6n-3).
Bivariable genetic associations using the mother and child genotypes suggested that the newborn metabolism had a greater capacity to synthesise the more highly unsaturated omega-6 than the more highly unsaturated omega-3 fatty acids. Nevertheless, despite the immaturity of the neonate, there was evidence that synthesis of DHA was occurring. However, by 7 years, no associations were observed with the maternal genotype.
This suggested that the children's fatty acid levels were only related to their own metabolism with no apparent lasting influences of the in utero environment.