title: Variation in the FADS1/2 gene cluster alters plasma n-6 PUFA and is weakly associated with hsCRP levels in healthy young adults.
abstract: BACKGROUND
  Past research has reported that single nucleotide polymorphisms (SNPs) in fatty acid desaturase 1 and 2 (FADS1/2) can influence plasma fatty acid (FA) profiles. Changes in FA profiles are known to influence inflammatory processes; therefore both FA and SNPs in FADS1/2 may affect inflammation. The goals of this study were to (i) examine the relationships between individual n-6 FA and estimates of FA desaturation with circulating high sensitivity C-reactive protein (hsCRP) levels, and (ii) determine whether SNPs in FADS1/2 are associated with changes in hsCRP.
  
  
  METHODS
  FA and hsCRP were measured in fasted plasma samples from 878 healthy young adults (20-29yrs). Circulating levels of plasma linoleic (LA), γ-linolenic (GLA), dihomo-γ-linolenic (DGLA) and arachidonic (AA) acids were measured by gas chromatography and used to calculate desaturase indices for FADS1/2. Nineteen SNPs in FADS1/2 were genotyped in all subjects and six (rs174579, rs174593, rs174626, rs526126, rs968567 and rs17831757) were further analyzed.
  
  
  RESULTS
  Significant inverse associations were found between LA and hsCRP (p=8.55×10(-9)) and the FADS1 desaturase index and hsCRP (p=4.41×10(-6)). A significant positive association was found between DGLA and hsCRP (p=9.10×10(-11)). Several SNPs were associated with circulating levels of individual FA and desaturase indices, with minor allele carriers having lower AA levels and reduced desaturase indices. A single SNP in FADS2 (rs526126) was weakly associated with hsCRP (p=0.05).
  
  
  CONCLUSIONS
  This study highlights the relationships between FA and hsCRP, and confirms that FA are strongly influenced by SNPs in FADS1/2. Furthermore, we found weak evidence that SNPs in FADS1/2 may influence hsCRP levels in young adults.
authors.affiliation: Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, ON, Canada N1G 2W1. Electronic address: kroke@uoguelph.ca.
authors.forename: Kaitlin
authors.initials: K
authors.lastname: Roke
authors.forename: Jessica C
authors.initials: JC
authors.lastname: Ralston
authors.forename: Salma
authors.initials: S
authors.lastname: Abdelmagid
authors.forename: Daiva E
authors.initials: DE
authors.lastname: Nielsen
authors.forename: Alaa
authors.initials: A
authors.lastname: Badawi
authors.forename: Ahmed
authors.initials: A
authors.lastname: El-Sohemy
authors.forename: David W L
authors.initials: DW
authors.lastname: Ma
authors.forename: David M
authors.initials: DM
authors.lastname: Mutch
mesh_terms: D000328:Adult; D002097:C-Reactive Protein / Q000378:metabolism*; D000090943:Delta-5 Fatty Acid Desaturase; D044943:Fatty Acid Desaturases / Q000235:genetics*; D043371:Fatty Acids, Omega-6 / Q000097:blood*; D005260:Female; D005787:Gene Frequency; D056726:Genetic Association Studies; D005838:Genotype; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D005810:Multigene Family; D020641:Polymorphism, Single Nucleotide; D055815:Young Adult
chemical_list: D000090943:Delta-5 Fatty Acid Desaturase; D043371:Fatty Acids, Omega-6; D002097:C-Reactive Protein; D044943:Fatty Acid Desaturases; C000716847:FADS1 protein, human; C533241:FADS2 protein, human
keywords: AA; BMI; DGLA; Dihomo-γ-linolenic acid; FA; FADS1, FADS2; FADS1/2; FFQ; Fatty acid desaturase; GLA; High sensitivity C-reactive protein; Inflammation; LA; Linolenic acid; PUFA; SNPs; Single nucleotide polymorphism; TNH; Toronto Nutrigenomics and Health Study; arachidonic acid; body mass index; dihomo-γ-linolenic acid; fatty acid desaturase 1 and 2; fatty acid desaturase gene cluster; fatty acids; food frequency questionnaire; high sensitivity C-reactive protein; hsCRP; linoleic acid; polyunsaturated fatty acids; single nucleotide polymorphisms; tSNPs; tag SNPs; γ-linolenic acid