• A Low Glycaemic Index Diet in Pregnancy Induces DNA Methylation Variation in Blood of Newborns: Results from the ROLO Randomised Controlled Trial.

      Geraghty, Aisling A; Sexton-Oates, Alexandra; O'Brien, Eileen C; Alberdi, Goiuri; Fransquet, Peter; Saffery, Richard; McAuliffe, Fionnuala M; National Maternity Hospital Holles Street Dublin, University College Dublin, Cancer and Disease Epigenetics, Murdoch Children's Research Institute, Melbourne, Victoria, Aus, Department of Paediatrics, University of Melbourne, Victoria, Aus (MDPI, 2018-04-06)
      The epigenetic profile of the developing fetus is sensitive to environmental influence. Maternal diet has been shown to influence DNA methylation patterns in offspring, but research in humans is limited. We investigated the impact of a low glycaemic index dietary intervention during pregnancy on offspring DNA methylation patterns using a genome-wide methylation approach. Sixty neonates were selected from the ROLO (Randomised cOntrol trial of LOw glycaemic index diet to prevent macrosomia) study: 30 neonates from the low glycaemic index intervention arm and 30 from the control, whose mothers received no specific dietary advice. DNA methylation was investigated in 771,484 CpG sites in free DNA from cord blood serum. Principal component analysis and linear regression were carried out comparing the intervention and control groups. Gene clustering and pathway analysis were also explored. Widespread variation was identified in the newborns exposed to the dietary intervention, accounting for 11% of the total level of DNA methylation variation within the dataset. No association was found with maternal early-pregnancy body mass index (BMI), infant sex, or birthweight. Pathway analysis identified common influences of the intervention on gene clusters plausibly linked to pathways targeted by the intervention, including cardiac and immune functioning. Analysis in 60 additional samples from the ROLO study failed to replicate the original findings. Using a modest-sized discovery sample, we identified preliminary evidence of differential methylation in progeny of mothers exposed to a dietary intervention during pregnancy.
    • Maternal and fetal blood lipid concentrations during pregnancy differ by maternal body mass index: findings from the ROLO study.

      Geraghty, Aisling A; Alberdi, Goiuri; O'Sullivan, Elizabeth J; O'Brien, Eileen C; Crosbie, Brenda; Twomey, Patrick J; McAuliffe, Fionnuala M; 1 UCD Perinatal Research Centre, Obstetrics and Gynaecology, School of Medicine, University College Dublin, National Maternity Hospital, Dublin 2, Ireland. 2 Clinical Chemistry, St. Vincent's University Hospital, Dublin 4, Ireland. 3 UCD School of Medicine, University College Dublin, Dublin, Ireland. 4 UCD Perinatal Research Centre, Obstetrics and Gynaecology, School of Medicine, University College Dublin, National Maternity Hospital, Dublin 2, Ireland. (Biomed Central, 2017-10-16)
      Pregnancy is a time of altered metabolic functioning and maternal blood lipid profiles change to accommodate the developing fetus. While these changes are physiologically necessary, blood lipids concentrations have been associated with adverse pregnancy outcomes such as gestational diabetes, pregnancy-induced hypertension and high birth weight. As blood lipids are not routinely measured during pregnancy, there is limited information on what is considered normal during pregnancy and in fetal blood. Data from 327 mother-child pairs from the ROLO longitudinal birth cohort study were analysed. Fasting total cholesterol and triglycerides were measured in early and late pregnancy and fetal cord blood. Intervals were calculated using the 2.5th, 50th and 97.5th centile. Data was stratified based on maternal body mass index (BMI) measured during early pregnancy. Differences in blood lipids between BMI categories were explored using ANOVA and infant outcomes of macrosomia and large-for-gestational-age (LGA) were explored using independent student T-tests and binary logistic regression. All maternal blood lipid concentrations increased significantly from early to late pregnancy. In early pregnancy, women with a BMI < 25 kg/m Blood lipid concentrations increase during pregnancy and differ by maternal BMI. These intervals could help to inform the development of references for blood lipid concentrations during pregnancy.