Anna Bergström, Carrie V. Breton, Marie-France Hivert, Oscar H. Franco, Roy Miodini Nilsen, Leanne K. Küpers, Kelly M. Bakulski, Mariona Pinart, Eva Corpeleijn, Erik Melén, Paul Yousefi, Symen Ligthart, Cilla Söderhäll, Monica Cheng Munthe-Kaas, Hasan Arshad, Donglei Hu, Pieter van der Vlies, Göran Pershagen, Bilal M. Quraishi, Jörg Tost, Ashok Kumar, Inger Kull, Nathanaël Lemonnier, Ahmad Vaez, Albert Hofman, Wilfried Karmaus, Sara E. Benjamin Neelon, Joyce B. J. van Meurs, Susan Ewart, Celeste Eng, Cathrine Hoyo, M. Daniele Fallin, Juha Kere, Andrea A. Baccarelli, Olena Gruzieva, Henning Tiemeier, Allan C. Just, Isabella Annesi-Maesano, Rebecca C Richmond, Andrew P. Feinberg, Gemma C Sharp, Christina A. Markunas, Carlos Ruiz, Charles Auffray, Harold Snieder, Simon Kebede Merid, Nour Baïz, Josep M. Antó, Brenda Eskenazi, Susan K. Murphy, Hongmei Zhang, Fahimeh Falahi, Christine Ladd-Acosta, Martine Vrijheid, Jin Yao, Sarah E. Reese, Marie José Saurel-Coubizolles, Karen Huen, Zdenko Herceg, Tianyuan Wang, Lisa F. Barcellos, Siri E. Håberg, Cheng-Jian Xu, Marjan Kerkhof, Nina Holland, Stephanie J. London, John W. Holloway, Barbara Heude, Hector Hernandez-Vargas, Mariona Bustamante, Marie-Aline Charles, Augusto A. Litonjua, Tom R. Gaunt, Dawn L. DeMeo, Abbas Dehghan, Zongli Xu, Bernard F. Fuemmeler, Caroline L Relton, Jordi Sunyer, Juan R. González, Jie Ren, Marjolein J. Peters, Ulrike Gehring, Sam S. Oh, Jack A. Taylor, Soesma A Jankipersadsing, Wenche Nystad, Matthew W. Gillman, Asa Bradman, Wendy L. McArdle, Vincent W. V. Jaddoe, George Davey Smith, Dirkje S. Postma, Magnus Wickman, Johanna Lepeule, Bonnie R. Joubert, Bert Brunekreef, Stefano Guerra, Liesbeth Duijts, Gerard H. Koppelman, Janine F. Felix, Esteban G. Burchard, Allen J. Wilcox, Michael C. Wu, Lucas A. Salas, Akram Ghantous, Epidemiology, Erasmus MC other, Pediatric Surgery, Pediatrics, Internal Medicine, Gastroenterology & Hepatology, dIRAS RA-2, Risk Assessment, Groningen Research Institute for Asthma and COPD (GRIAC), Reproductive Origins of Adult Health and Disease (ROAHD), Lifestyle Medicine (LM), and Life Course Epidemiology (LCE)
Epigenetic modifications, including DNA methylation, represent a potential mechanism for environmental impacts on human disease. Maternal smoking in pregnancy remains an important public health problem that impacts child health in a myriad of ways and has potential lifelong consequences. The mechanisms are largely unknown, but epigenetics most likely plays a role. We formed the Pregnancy And Childhood Epigenetics (PACE) consortium and meta-analyzed, across 13 cohorts (n = 6,685), the association between maternal smoking in pregnancy and newborn blood DNA methylation at over 450,000 CpG sites (CpGs) by using the Illumina 450K BeadChip. Over 6,000 CpGs were differentially methylated in relation to maternal smoking at genome-wide statistical significance (false discovery rate, 5%), including 2,965 CpGs corresponding to 2,017 genes not previously related to smoking and methylation in either newborns or adults. Several genes are relevant to diseases that can be caused by maternal smoking (e.g., orofacial clefts and asthma) or adult smoking (e.g., certain cancers). A number of differentially methylated CpGs were associated with gene expression. We observed enrichment in pathways and processes critical to development. In older children (5 cohorts, n = 3,187), 100% of CpGs gave at least nominal levels of significance, far more than expected by chance (p value < 2.2 × 10−16). Results were robust to different normalization methods used across studies and cell type adjustment. In this large scale meta-analysis of methylation data, we identified numerous loci involved in response to maternal smoking in pregnancy with persistence into later childhood and provide insights into mechanisms underlying effects of this important exposure. The BAMSE cohort was supported by The Swedish Research Council, The Swedish Heart-Lung Foundation, Freemason Child House Foundation in Stockholm, MeDALL (Mechanisms of the Development of ALLergy), a collaborative project conducted within the European Union (grant agreement No. 261357), Centre for Allergy Research, Stockholm County Council (ALF), Swedish foundation for strategic research (SSF, RBc08-0027, EpiGene project), the Strategic Research Programme (SFO) in Epidemiology at Karolinska Institutet, The Swedish Research Council Formas and the Swedish Environment Protection Agency.