title: The heritability and patterns of DNA methylation in normal human colorectum.
abstract: DNA methylation (DNAm) has been linked to changes in chromatin structure, gene expression and disease. The DNAm level can be affected by genetic variation; although, how this differs by CpG dinucleotide density and genic location of the DNAm site is not well understood. Moreover, the effect of disease causing variants on the DNAm level in a tissue relevant to disease has yet to be fully elucidated. To this end, we investigated the phenotypic profiles, genetic effects and regional genomic heritability for 196080 DNAm sites in healthy colorectum tissue from 132 unrelated Colombian individuals. DNAm sites in regions of low-CpG density were more variable, on average more methylated and were more likely to be significantly heritable when compared with DNAm sites in regions of high-CpG density. DNAm sites located in intergenic regions had a higher mean DNAm level and were more likely to be heritable when compared with DNAm sites in the transcription start site (TSS) of a gene expressed in colon tissue. Within CpG-dense regions, the propensity of the DNAm level to be heritable was lower in the TSS of genes expressed in colon tissue than in the TSS of genes not expressed in colon tissue. In addition, regional genetic variation was associated with variation in local DNAm level no more frequently for DNAm sites within colorectal cancer risk regions than it was for DNAm sites outside such regions. Overall, DNAm sites located in different genomic contexts exhibited distinguishable profiles and may have a different biological function.
authors.affiliation: The Roslin Institute, The University of Edinburgh, Edinburgh, EH25 9RG, UK.
authors.forename: Amy
authors.initials: A
authors.lastname: Rowlatt
authors.affiliation: Grupo de Investigación Epidemiológica and.
authors.forename: Gustavo
authors.initials: G
authors.lastname: Hernández-Suárez
authors.affiliation: Grupo de Investigación en Biología del Cáncer, Instituto Nacional de Cancerología, Bogotá, Colombia.|Departamento de Química, Universidad Nacional de Colombia, Bogotá, Colombia.
authors.forename: María Carolina
authors.initials: MC
authors.lastname: Sanabria-Salas
authors.affiliation: Grupo de Investigación en Biología del Cáncer, Instituto Nacional de Cancerología, Bogotá, Colombia.|Departamento de Química, Universidad Nacional de Colombia, Bogotá, Colombia.
authors.forename: Martha
authors.initials: M
authors.lastname: Serrano-López
authors.affiliation: The Roslin Institute, The University of Edinburgh, Edinburgh, EH25 9RG, UK.
authors.forename: Konrad
authors.initials: K
authors.lastname: Rawlik
authors.affiliation: Laboratorio Genética Molecular, Hospital General Universitario de Elche, 03203 Elche, Alicante, Spain.
authors.forename: Eva
authors.initials: E
authors.lastname: Hernandez-Illan
authors.affiliation: Pathology, Alicante University Hospital, Alicante, Spain and.
authors.forename: Cristina
authors.initials: C
authors.lastname: Alenda
authors.affiliation: Laboratorio Genética Molecular, Hospital General Universitario de Elche, 03203 Elche, Alicante, Spain.
authors.forename: Adela
authors.initials: A
authors.lastname: Castillejo
authors.affiliation: Laboratorio Genética Molecular, Hospital General Universitario de Elche, 03203 Elche, Alicante, Spain.
authors.forename: Jose Luis
authors.initials: JL
authors.lastname: Soto
authors.affiliation: The Roslin Institute, The University of Edinburgh, Edinburgh, EH25 9RG, UK.|MRC Human Genetics Unit, MRC Institute of Genetics and Molecular Medicine, The University of Edinburgh, Edinburgh, EH4 2XU, UK.
authors.forename: Chris S
authors.initials: CS
authors.lastname: Haley
authors.affiliation: The Roslin Institute, The University of Edinburgh, Edinburgh, EH25 9RG, UK, albert.tenesa@ed.ac.uk.|MRC Human Genetics Unit, MRC Institute of Genetics and Molecular Medicine, The University of Edinburgh, Edinburgh, EH4 2XU, UK.
authors.forename: Albert
authors.initials: A
authors.lastname: Tenesa
mesh_terms: D003106:Colon / Q000378:metabolism*; D003111:Colonic Polyps / Q000235:genetics / Q000378:metabolism; D018899:CpG Islands / Q000235:genetics; D019175:DNA Methylation / Q000235:genetics*; D044127:Epigenesis, Genetic; D005260:Female; D005786:Gene Expression Regulation; D015894:Genome, Human; D023281:Genomics; D006801:Humans; D008297:Male; D020411:Oligonucleotide Array Sequence Analysis; D011401:Promoter Regions, Genetic; D012007:Rectum / Q000378:metabolism*