title: Cardiovascular disease risk factors and DNA methylation at the LINE-1 repeat region in peripheral blood from Samoan Islanders.
abstract: Lower levels of LINE-1 methylation in peripheral blood have been previously associated with risk of developing non-communicable conditions, the most well-explored of these being cancer, although recent research has begun to link altered LINE-1 methylation and cardiovascular disease. We examined the relationship between LINE-1 methylation and factors associated with metabolic and cardiovascular diseases through quantitative bisulfite pyrosequencing in DNA from peripheral blood samples from participants of the Samoan Family Study of Overweight and Diabetes (2002-03). The sample included 355 adult Samoans (88 men and 267 women) from both American Samoa and Samoa. In a model including all sample participants, men had significantly higher LINE-1 methylation levels than women (p=0.04), and lower levels of LINE-1 methylation were associated with higher levels of fasting LDL (p=0.02) and lower levels of fasting HDL (p=0.009). The findings from this study confirm that DNA "global" hypomethylation, (as measured by methylation at LINE-1 repeats) observed previously in cardiovascular disease is associated with altered levels of LDL and HDL in peripheral blood. Additionally, these findings strongly argue the need for further research, particularly including prospective studies, in order to understand the relationship between LINE-1 DNA methylation measured in blood and risk factors for cardiovascular disease.
authors.affiliation: Department of Pathology and Laboratory Medicine, International Health Institute, Public Health Program, Brown University, Providence, RI, USA. haley.menard@gmail.com　
authors.forename: Haley L
authors.initials: HL
authors.lastname: Cash
authors.forename: Stephen T
authors.initials: ST
authors.lastname: McGarvey
authors.forename: E Andrés
authors.initials: EA
authors.lastname: Houseman
authors.forename: Carmen J
authors.initials: CJ
authors.lastname: Marsit
authors.forename: Nicola L
authors.initials: NL
authors.lastname: Hawley
authors.forename: Geralyn M
authors.initials: GM
authors.lastname: Lambert-Messerlian
authors.forename: Satupaitea
authors.initials: S
authors.lastname: Viali
authors.forename: John
authors.initials: J
authors.lastname: Tuitele
authors.forename: Karl T
authors.initials: KT
authors.lastname: Kelsey
mesh_terms: D000328:Adult; D001786:Blood Glucose; D002318:Cardiovascular Diseases / Q000235:genetics*; D008076:Cholesterol, HDL / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood; D004247:DNA / Q000097:blood; D019175:DNA Methylation; D044127:Epigenesis, Genetic; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D020084:Long Interspersed Nucleotide Elements / Q000235:genetics*; D008297:Male; D008659:Metabolic Diseases / Q000235:genetics; D012307:Risk Factors; D018947:Samoa
chemical_list: D001786:Blood Glucose; D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D004247:DNA