title: Genetic polymorphisms that affect selenium status and response to selenium supplementation in United Kingdom pregnant women.
abstract: BACKGROUND
  Low selenium status in pregnancy has been associated with a number of adverse conditions. In nonpregnant populations, the selenium status or response to supplementation has been associated with polymorphisms in dimethylglycine dehydrogenase (DMGDH), selenoprotein P (SEPP1) and the glutathione peroxidases [cytosolic glutathione peroxidase (GPx1) and phospholipid glutathione peroxidase (GPx4)].
  
  
  OBJECTIVE
  We hypothesized that, in pregnant women, these candidate polymorphisms would be associated with selenium status in early pregnancy, its longitudinal change, and the interindividual response to selenium supplementation at 60 μg/d.
  
  
  METHODS
  With the use of stored samples and data from the United Kingdom Selenium in Pregnancy Intervention (SPRINT) study in 227 pregnant women, we carried out genetic-association studies, testing for associations between selenium status, its longitudinal change, and response to supplementation and common genetic variation in DMGDH (rs921943), SEPP1 (rs3877899 and rs7579), GPx1 (rs1050450) and GPx4 (rs713041). Selenium status was represented by the concentration of whole-blood selenium at 12 and 35 wk of gestation, the concentration of toenail selenium at 16 wk of gestation, and plasma glutathione peroxidase (GPx3) activity at 12 and 35 wk of gestation.
  
  
  RESULTS
  Our results showed that DMGDH rs921943 was significantly associated with the whole-blood selenium concentration at 12 wk of gestation (P = 0.032), which explained ≤2.0% of the variance. This association was replicated with the use of toenail selenium (P = 0.043). In unsupplemented women, SEPP1 rs3877899 was significantly associated with the percentage change in whole-blood selenium from 12 to 35 wk of gestation (P = 0.005), which explained 8% of the variance. In supplemented women, SEPP1 rs3877899 was significantly associated with the percentage change in GPx3 activity from 12 to 35 wk of gestation (P = 0.01), which explained 5.3% of the variance. Selenium status was not associated with GPx1, GPx4, or SEPP1 rs7579.
  
  
  CONCLUSIONS
  In agreement with previous studies, we show that the genetic variant rs921943 in DMGDH is significantly associated with selenium status in United Kingdom pregnant women. Notably, our study shows that women who carry the SEPP1 rs3877899 A allele are better able to maintain selenium status during pregnancy, and their GPx3 activity increases more with supplementation, which suggests better protection from low selenium status. The SPRINT study was registered at www.isrctn.com as ISRCTN37927591.
authors.affiliation: Department of Endocrinology and Metabolism, the First Hospital of China Medical University, Shenyang, China; Department of Nutritional Sciences, Faculty of Health and Medical Sciences, University of Surrey, Guildford, United Kingdom;
authors.forename: Jinyuan
authors.initials: J
authors.lastname: Mao
authors.affiliation: School of Medical Science, Griffith Health Institute, Griffith University, Queensland, Australia; and.
authors.forename: Jessica J
authors.initials: JJ
authors.lastname: Vanderlelie
authors.affiliation: School of Medical Science, Griffith Health Institute, Griffith University, Queensland, Australia; and.
authors.forename: Anthony V
authors.initials: AV
authors.lastname: Perkins
authors.affiliation: Nuffield Department of Obstetrics and Gynecology, University of Oxford, Oxford, United Kingdom.
authors.forename: Christopher W G
authors.initials: CW
authors.lastname: Redman
authors.affiliation: Department of Nutritional Sciences, Faculty of Health and Medical Sciences, University of Surrey, Guildford, United Kingdom;
authors.forename: Kourosh R
authors.initials: KR
authors.lastname: Ahmadi
authors.affiliation: Department of Nutritional Sciences, Faculty of Health and Medical Sciences, University of Surrey, Guildford, United Kingdom; m.rayman@surrey.ac.uk.
authors.forename: Margaret P
authors.initials: MP
authors.lastname: Rayman
mesh_terms: D003677:Deficiency Diseases / Q000235:genetics* / Q000517:prevention & control; D019587:Dietary Supplements; D050893:Dimethylglycine Dehydrogenase / Q000235:genetics*; D005260:Female; D056726:Genetic Association Studies; D005979:Glutathione Peroxidase / Q000235:genetics; D006801:Humans; D009262:Nails / Q000378:metabolism; D009752:Nutritional Status / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide; D011247:Pregnancy; D011248:Pregnancy Complications / Q000235:genetics / Q000517:prevention & control; D012643:Selenium / Q000097:blood* / Q000172:deficiency / Q000378:metabolism / Q000627:therapeutic use; D051149:Selenoprotein P / Q000235:genetics*; D006113:United Kingdom
chemical_list: D051149:Selenoprotein P; D005979:Glutathione Peroxidase; D050893:Dimethylglycine Dehydrogenase; D012643:Selenium
keywords: DMGDH; SEPP1; polymorphisms; pregnancy; selenium status