title: The association of maternal ACE A11860G with small for gestational age babies is modulated by the environment and by fetal sex: a multicentre prospective case-control study.
abstract: We aimed to determine whether the ACE A11860G genotype is associated with small for gestational age babies (SGA) and to determine whether the association is affected by environmental factors and fetal sex. Overall, 3234 healthy nulliparous women with singleton pregnancies, their partners and babies were prospectively recruited in Adelaide, Australia and Auckland, New Zealand. Data analyses were confined to 2121 Caucasian parent-infant trios, among which 216 were pregnancies with SGA infants and 1185 were uncomplicated pregnancies. Women with the ACE A11860G GG genotype in the combined and Adelaide cohorts had increased risk for SGA [odds ratios (OR) 1.5, 95% confidence interval (CI) 1.1-2.1 and OR 2.0, 95% CI 1.3-3.3, respectively) and delivered lighter babies (P = 0.02; P = 0.007, respectively) compared with those with AA/AG genotypes. The maternal ACE A11860G GG genotype was associated with higher maternal plasma ACE concentration at 15 weeks' gestation than AA/AG genotypes (P < 0.001). When the Adelaide cohort was stratified by maternal socio-economic index (SEI) and pre-pregnancy green leafy vegetable intake, the ACE A11860G GG genotype was only associated with an increased risk for SGA (OR 4.9, 95% CI 1.8-13.4 and OR 3.3, 95% CI 1.6-7.0, respectively) and a reduction in customized birthweight centile (P = 0.006 and P = 0.03) if superimposed on maternal SEI <34 or pre-pregnancy green leafy vegetable intake <1 serve/day. Furthermore, the associations of maternal ACE A11860G with customized birthweight centile observed among Adelaide women with SEI <34 or pre-pregnancy green leafy vegetable intake <1 serve/day were female specific. The current study identified a novel association of maternal ACE A11860G with SGA. More interestingly, this association was modified by environmental factors and fetal sex, suggesting ACE A11860G-environment-fetal sex interactions. Trial Registry Name: Screening nulliparous women to identify the combinations of clinical risk factors and/or biomarkers required to predict pre-eclampsia, SGA babies and spontaneous preterm birth. URL: http://www.anzctr.org.au.
  
  
  BACKGROUND
  ACTRN12607000551493.
authors.affiliation: Robinson Institute, University of Adelaide, Adelaide, SA 5005, Australia.
authors.forename: Ang
authors.initials: A
authors.lastname: Zhou
authors.forename: Gustaaf A
authors.initials: GA
authors.lastname: Dekker
authors.forename: Eugenie R
authors.initials: ER
authors.lastname: Lumbers
authors.forename: Shalem Y
authors.initials: SY
authors.lastname: Leemaqz
authors.forename: Steven D
authors.initials: SD
authors.lastname: Thompson
authors.forename: Gary
authors.initials: G
authors.lastname: Heinemann
authors.forename: Lesley M E
authors.initials: LM
authors.lastname: McCowan
authors.forename: Claire T
authors.initials: CT
authors.lastname: Roberts
mesh_terms: D000328:Adult; D001315:Australia; D016022:Case-Control Studies; D005260:Female; D059647:Gene-Environment Interaction; D005838:Genotype; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D007236:Infant, Small for Gestational Age; D008297:Male; D009520:New Zealand; D007703:Peptidyl-Dipeptidase A / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide; D011247:Pregnancy; D011446:Prospective Studies; D012307:Risk Factors; D012737:Sex Factors; D044465:White People
chemical_list: C488034:ACE protein, human; D007703:Peptidyl-Dipeptidase A
keywords: ACE A11860G; fetal sex; pre-pregnancy green leafy vegetable intake; small for gestational age; socio-economic index