title: Genetic variants of the fatty acid desaturase gene cluster predict amounts of red blood cell docosahexaenoic and other polyunsaturated fatty acids in pregnant women: findings from the Avon Longitudinal Study of Parents and Children.
abstract: BACKGROUND
  Blood and tissue long-chain polyunsaturated fatty acid (LC-PUFA) amounts, which have been associated with early development and lifelong health, depend on dietary intake and endogenous conversion of precursor fatty acids (FAs) by the enzymes Δ⁵-desaturase and Δ⁶-desaturase. Polymorphisms in the desaturase encoding genes FADS1 and FADS2 have been associated with several n-6 (omega-6) and n-3 (omega-3) FAs and especially with arachidonic acid (AA) amounts. Associations with docosahexaenoic acid (DHA), which is considered particularly important for brain and retina development, are hardly existent.
  
  
  OBJECTIVE
  We explored the relation between FADS gene cluster polymorphisms and red blood cell (RBC) FA amounts in > 4000 pregnant women participating in the Avon Longitudinal Study of Parents and Children.
  
  
  METHODS
  Linear regression analysis of 17 single nucleotide polymorphisms (SNPs) in the FADS gene cluster was conducted with RBC phospholipid FAs from 6711 samples from 4457 women obtained throughout pregnancy (mean ± SD gestational age: 26.8 ± 8.2 wk).
  
  
  RESULTS
  Independent of dietary effects, the minor alleles were consistently positively associated with precursor FAs and negatively associated with LC-PUFAs and product:substrate ratios of the n-6 (AA:linoleic acid ratio) and n-3 (eicosapentaenoic acid:α-linolenic acid ratio) pathways. In contrast to previous studies, we also showed significant inverse associations with DHA. Similar but weaker associations were shown for the FADS3 SNP rs174455.
  
  
  CONCLUSIONS
  FADS genotypes influence DHA amounts in maternal RBC phospholipids and might affect the child's DHA supply during pregnancy. It is highly likely that a gene product of FADS3 has a desaturating activity.
authors.affiliation: Department of Pediatrics, Dr von Hauner Children's Hospital, University of Munich Medical Center, Munich, Germany. office.koletzko@med.uni-muenchen.de
authors.forename: Berthold
authors.initials: B
authors.lastname: Koletzko
authors.forename: Eva
authors.initials: E
authors.lastname: Lattka
authors.forename: Sonja
authors.initials: S
authors.lastname: Zeilinger
authors.forename: Thomas
authors.initials: T
authors.lastname: Illig
authors.forename: Colin
authors.initials: C
authors.lastname: Steer
mesh_terms: D000090943:Delta-5 Fatty Acid Desaturase; D004281:Docosahexaenoic Acids / Q000097:blood*; D004912:Erythrocytes / Q000737:chemistry*; D044943:Fatty Acid Desaturases / Q000235:genetics*; D005231:Fatty Acids, Unsaturated / Q000097:blood*; D005260:Female; D006801:Humans; D016014:Linear Models; D008137:Longitudinal Studies; D005810:Multigene Family; D020641:Polymorphism, Single Nucleotide; D011247:Pregnancy / Q000378:metabolism*
chemical_list: D000090943:Delta-5 Fatty Acid Desaturase; D005231:Fatty Acids, Unsaturated; D004281:Docosahexaenoic Acids; D044943:Fatty Acid Desaturases; C000716847:FADS1 protein, human; C533241:FADS2 protein, human; C545859:FADS3 protein, human