title: Placental genome and maternal-placental genetic interactions: a genome-wide and candidate gene association study of placental abruption.
abstract: While available evidence supports the role of genetics in the pathogenesis of placental abruption (PA), PA-related placental genome variations and maternal-placental genetic interactions have not been investigated. Maternal blood and placental samples collected from participants in the Peruvian Abruptio Placentae Epidemiology study were genotyped using Illumina's Cardio-Metabochip platform. We examined 118,782 genome-wide SNPs and 333 SNPs in 32 candidate genes from mitochondrial biogenesis and oxidative phosphorylation pathways in placental DNA from 280 PA cases and 244 controls. We assessed maternal-placental interactions in the candidate gene SNPS and two imprinted regions (IGF2/H19 and C19MC). Univariate and penalized logistic regression models were fit to estimate odds ratios. We examined the combined effect of multiple SNPs on PA risk using weighted genetic risk scores (WGRS) with repeated ten-fold cross-validations. A multinomial model was used to investigate maternal-placental genetic interactions. In placental genome-wide and candidate gene analyses, no SNP was significant after false discovery rate correction. The top genome-wide association study (GWAS) hits were rs544201, rs1484464 (CTNNA2), rs4149570 (TNFRSF1A) and rs13055470 (ZNRF3) (p-values: 1.11e-05 to 3.54e-05). The top 200 SNPs of the GWAS overrepresented genes involved in cell cycle, growth and proliferation. The top candidate gene hits were rs16949118 (COX10) and rs7609948 (THRB) (p-values: 6.00e-03 and 8.19e-03). Participants in the highest quartile of WGRS based on cross-validations using SNPs selected from the GWAS and candidate gene analyses had a 8.40-fold (95% CI: 5.8-12.56) and a 4.46-fold (95% CI: 2.94-6.72) higher odds of PA compared to participants in the lowest quartile. We found maternal-placental genetic interactions on PA risk for two SNPs in PPARG (chr3:12313450 and chr3:12412978) and maternal imprinting effects for multiple SNPs in the C19MC and IGF2/H19 regions. Variations in the placental genome and interactions between maternal-placental genetic variations may contribute to PA risk. Larger studies may help advance our understanding of PA pathogenesis.
authors.affiliation: Department of Epidemiology, Harvard School of Public Health, Boston, Massachusetts, United States of America; UMR AGAP (Amélioration Génétique et Adaptation des Plantes méditerranéennes et tropicales), CIRAD, Montpellier, France.
authors.forename: Marie
authors.initials: M
authors.lastname: Denis
authors.affiliation: Center for Perinatal Studies, Swedish Medical Center, Seattle, Washington, United States of America; Department of Epidemiology, School of Public Health, University of Washington, Seattle, Washington, United States of America.
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Enquobahrie
authors.affiliation: Department of Mathematics and Statistics, Georgetown University, Washington, D.C., United States of America.
authors.forename: Mahlet G
authors.initials: MG
authors.lastname: Tadesse
authors.affiliation: Department of Epidemiology, Harvard School of Public Health, Boston, Massachusetts, United States of America.
authors.forename: Bizu
authors.initials: B
authors.lastname: Gelaye
authors.affiliation: Sección de Post Grado, Facultad de Medicina Humana, Universidad San Martín de Porres, Lima, Peru; A.C. PROESA, Lima, Peru.
authors.forename: Sixto E
authors.initials: SE
authors.lastname: Sanchez
authors.affiliation: Department of Obstetrics and Gynecology, San Marcos University, Lima, Peru.
authors.forename: Manuel
authors.initials: M
authors.lastname: Salazar
authors.affiliation: Department of Obstetrics and Gynecology, College of Physicians and Surgeons, Columbia University Medical Center, New York, New York, United States of America; Department of Epidemiology, Mailman School of Public Health, Columbia University, New York, New York, United States of America.
authors.forename: Cande V
authors.initials: CV
authors.lastname: Ananth
authors.affiliation: Department of Epidemiology, Harvard School of Public Health, Boston, Massachusetts, United States of America.
authors.forename: Michelle A
authors.initials: MA
authors.lastname: Williams
mesh_terms: D000037:Abruptio Placentae / Q000235:genetics* / Q000473:pathology; D000328:Adult; D005260:Female; D020022:Genetic Predisposition to Disease; D055106:Genome-Wide Association Study / Q000379:methods*; D018392:Genomic Imprinting; D006801:Humans; D007335:Insulin-Like Growth Factor II / Q000235:genetics; D008928:Mitochondria / Q000235:genetics*; D010084:Oxidation-Reduction; D020641:Polymorphism, Single Nucleotide; D011247:Pregnancy; D062085:RNA, Long Noncoding; D055815:Young Adult
chemical_list: C094335:H19 long non-coding RNA; C035170:IGF2 protein, human; D062085:RNA, Long Noncoding; D007335:Insulin-Like Growth Factor II