Genome-wide association study of plasma N6 polyunsaturated fatty acids within the cohorts for heart and aging research in genomic epidemiology consortium.
BACKGROUND
Omega6 (n6) polyunsaturated fatty acids (PUFAs) and their metabolites are involved in cell signaling, inflammation, clot formation, and other crucial biological processes. Genetic components, such as variants of fatty acid desaturase (FADS) genes, determine the composition of n6 PUFAs.


RESULTS
To elucidate undiscovered biological pathways that may influence n6 PUFA composition, we conducted genome-wide association studies and meta-analyses of associations of common genetic variants with 6 plasma n6 PUFAs in 8631 white adults (55% women) across 5 prospective studies. Plasma phospholipid or total plasma fatty acids were analyzed by similar gas chromatography techniques. The n6 fatty acids linoleic acid (LA), γ-linolenic acid (GLA), dihomo-GLA, arachidonic acid, and adrenic acid were expressed as percentage of total fatty acids. We performed linear regression with robust SEs to test for single-nucleotide polymorphism-fatty acid associations, with pooling using inverse-variance-weighted meta-analysis. Novel regions were identified on chromosome 10 associated with LA (rs10740118; P=8.1×10(-9); near NRBF2), on chromosome 16 with LA, GLA, dihomo-GLA, and arachidonic acid (rs16966952; P=1.2×10(-15), 5.0×10(-11), 7.6×10(-65), and 2.4×10(-10), respectively; NTAN1), and on chromosome 6 with adrenic acid after adjustment for arachidonic acid (rs3134950; P=2.1×10(-10); AGPAT1). We confirmed previous findings of the FADS cluster on chromosome 11 with LA and arachidonic acid, and further observed novel genome-wide significant association of this cluster with GLA, dihomo-GLA, and adrenic acid (P=2.3×10(-72), 2.6×10(-151), and 6.3×10(-140), respectively).


CONCLUSIONS
Our findings suggest that along with the FADS gene cluster, additional genes may influence n6 PUFA composition.
Division of Biostatistics, School of Public Health, University of Minnesota, Minneapolis, MN.
Weihua
W
Guan
Laboratory Medicine & Pathology, University of Minnesota, Minneapolis, MN.
Brian T
BT
Steffen
Cardiovascular Health Research Unit, Department of Medicine, University of Washington, Seattle, WA.
Rozenn N
RN
Lemaitre
Department of Epidemiology and Nutrition, Harvard School of Public Health, Boston, MA.|School of Medicine and Pharmacology, University of Western Australia, Perth, Australia.
Jason H Y
JHY
Wu
Translational Gerontology Branch, National Institute on Aging, National Institutes of Health, Baltimore, MD.
Toshiko
T
Tanaka
Center for Public Health Genomics, Division of Biostatistics and Epidemiology, University of Virginia, Charlottesville, VA.
Ani
A
Manichaikul
Institute of Molecular Medicine, University of Texas Health Sciences Center in Houston, Houston, TX.
Millennia
M
Foy
Center for Public Health Genomics, Division of Biostatistics and Epidemiology, University of Virginia, Charlottesville, VA.
Stephen S
SS
Rich
Department of Epidemiology and Nutrition, Harvard School of Public Health, Boston, MA.
Lu
L
Wang
Department of Epidemiology, University of Texas Health Sciences Center in Houston, Houston, TX.
Jennifer A
JA
Nettleton
Division of Epidemiology and Community Health, School of Public Health, University of Minnesota, Minneapolis, MN.
Weihong
W
Tang
Institute of Molecular Medicine, University of Texas Health Sciences Center in Houston, Houston, TX.
Xiangjun
X
Gu
Geriatric Rehabilitation Unit, Azienda Sanitaria Firenze (ASF), Florence, Italy.
Stafania
S
Bandinelli
Department of Internal Medicine, University of New Mexico, Albuquerque, New Mexico.
Irena B
IB
King
Cardiovascular Health Research Unit, Department of Medicine, University of Washington, Seattle, WA.
Barbara
B
McKnight
Cardiovascular Health Research Unit, Departments of Medicine, Epidemiology and Health Services, University of Washington, Seattle, WA.|Group Health Research Institute, Group Health Cooperative, Seattle, WA.
Bruce M
BM
Psaty
Cardiovascular Health Research Unit, Departments of Medicine, Epidemiology and Health Services, University of Washington, Seattle, WA.
David
D
Siscovick
Department of Medicine, Brigham and Women's Hospital, Harvard Medical School & Boston VA Healthcare System, Boston, MA.
Luc
L
Djousse
Cedars-Sinai Medical Center, Los Angeles, CA.
Yii-Der Ida
YI
Chen
Translational Gerontology Branch, National Institute on Aging, National Institutes of Health, Baltimore, MD.
Luigi
L
Ferrucci
Institute of Molecular Medicine, University of Texas Health Sciences Center in Houston, Houston, TX.|Department of Epidemiology, University of Texas Health Sciences Center in Houston, Houston, TX.
Myriam
M
Fornage
Division of Cardiovascular Medicine, Brigham and Women's Hospital and Harvard Medical School; Department of Epidemiology, Harvard School of Public Health, Boston, MA.
Dariush
D
Mozafarrian
Laboratory Medicine & Pathology, University of Minnesota, Minneapolis, MN.
Michael Y
MY
Tsai
Division of Epidemiology and Community Health, School of Public Health, University of Minnesota, Minneapolis, MN.
Lyn M
LM
Steffen
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000097:blood* / Q000235:genetics*; D002879:Chromosomes, Human, Pair 10 / Q000235:genetics; D002885:Chromosomes, Human, Pair 16 / Q000235:genetics; D002896:Chromosomes, Human, Pair 6 / Q000235:genetics; D044943:Fatty Acid Desaturases / Q000235:genetics; D043371:Fatty Acids, Omega-6 / Q000097:blood*; D005260:Female; D055106:Genome-Wide Association Study; D023281:Genomics; D006331:Heart Diseases / Q000097:blood / Q000453:epidemiology / Q000235:genetics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D011446:Prospective Studies; D017422:Sequence Analysis, DNA
D043371:Fatty Acids, Omega-6; D044943:Fatty Acid Desaturases
N6 fatty acids; epidemiology; genome-wide association study; polyunsaturated fatty acids