title: Genetic and environmental impacts on DNA methylation levels in twins.
abstract: Epigenetics describes the study of cellular modifications that can modify the expression of genes without changing the DNA sequence. DNA methylation is one of the most stable and prevalent epigenetic mechanisms. Twin studies have been a valuable model for unraveling the genetic and epigenetic epidemiology of complex traits, and now offer a potential to dissect the factors that impact DNA methylation variability and its biomedical significance. The twin design specifically allows for the study of genetic, environmental and lifestyle factors, and their potential interactions, on epigenetic profiles. Furthermore, genetically identical twins offer a unique opportunity to assess nongenetic impacts on epigenetic profiles. Here, we summarize recent findings from twin studies of DNA methylation profiles across tissues, to define current knowledge regarding the genetic and nongenetic factors that influence epigenetic variation.
authors.affiliation: Department of Twin Research & Genetic Epidemiology, King's College, London, UK.
authors.forename: Idil
authors.initials: I
authors.lastname: Yet
authors.affiliation: Department of Twin Research & Genetic Epidemiology, King's College, London, UK.
authors.forename: Pei-Chien
authors.initials: PC
authors.lastname: Tsai
authors.affiliation: Department of Twin Research & Genetic Epidemiology, King's College, London, UK.
authors.forename: Juan E
authors.initials: JE
authors.lastname: Castillo-Fernandez
authors.affiliation: Department of Twin Research & Genetic Epidemiology, King's College, London, UK.
authors.forename: Elena
authors.initials: E
authors.lastname: Carnero-Montoro
authors.affiliation: Department of Twin Research & Genetic Epidemiology, King's College, London, UK.
authors.forename: Jordana T
authors.initials: JT
authors.lastname: Bell
mesh_terms: D019175:DNA Methylation; D044127:Epigenesis, Genetic; D059647:Gene-Environment Interaction; D014644:Genetic Variation; D006801:Humans; D008957:Models, Genetic; D018433:Twin Studies as Topic; D014427:Twins / Q000235:genetics*
keywords: DNA methylation; epigenetics; heritability; methylation quantitative trait loci; twin studies