Folate nutritional genetics and risk for hypertension in an elderly population sample.
OBJECTIVE
118 elderly participants (65-90 years) were assessed for any relationship between folate, related genes and hypertension.


METHODS
Six B-vitamin-related SNPs were genotyped in 80 normotensive and 38 hypertensive subjects.


RESULTS
Of six polymorphisms (677C>T-MTHFR, 1298A>C-MTHFR, 80G>A-RFC, 2756A>G-MS, 66A>G- MSR, 19bpDHFR and 1561C>T-GCPII), only 677C>T-MTHFR was a significant risk for hypertension: OR 1.89; 95% CI 1.07-3.32 (chi2 p = 0.038). Additionally, hypertensive subjects had a significantly lower intake of dietary folate than normotensive individuals (p = 0.0221), although this did not markedly alter blood metabolite levels. Several significant linear associations between dietary folate and related blood metabolites were found in normotensive subjects (p < 0.001 for Hcy, red cell and serum folate) and were as predicted on an a priori basis -- generally weaker associations existed in hypertensive subjects (p < 0.05 for serum folate). This was true for data examined collectively or by genotype. Multiple-regression analysis for diastolic or systolic blood pressure showed significant interaction for gender and folate intake (p = 0.014 and 0.019, respectively). In both cases this interaction occurred only in females, with higher folate intake associated with decreased blood pressure. Regressing diastolic blood pressure and 677C>T-MTHFR genotype showed significance (males; p = 0.032) and borderline significance (all subjects).


CONCLUSIONS
Dietary folate and 677C>T-MTHFR genotype may modify blood pressure.
School of Environmental and Life Sciences, University of Newcastle, Ourimbah, NSW, Australia.
Xiaowei
X
Ng
Lyndell
L
Boyd
Lisa
L
Dufficy
Nenad
N
Naumovski
Barbara
B
Blades
Cheryl
C
Travers
Peter
P
Lewis
Jonathon
J
Sturm
Zoë
Z
Yates
Maureen
M
Townley-Jones
Paul
P
Roach
Martin
M
Veysey
Mark
M
Lucock
D013766:5-Methyltetrahydrofolate-Homocysteine S-Methyltransferase / Q000235:genetics; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D005287:Ferredoxin-NADP Reductase / Q000235:genetics; D005492:Folic Acid / Q000097:blood / Q000235:genetics*; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D006801:Humans; D006973:Hypertension / Q000235:genetics*; D008297:Male; D026901:Membrane Transport Proteins / Q000235:genetics; D042965:Methylenetetrahydrofolate Reductase (NADPH2) / Q000235:genetics; D054647:Nutrigenomics; D020641:Polymorphism, Single Nucleotide; D011153:Population; D058978:Reduced Folate Carrier Protein; D012307:Risk Factors
D026901:Membrane Transport Proteins; D058978:Reduced Folate Carrier Protein; C548699:SLC19A1 protein, human; D005492:Folic Acid; C111241:methionine synthase reductase; D005287:Ferredoxin-NADP Reductase; D042965:Methylenetetrahydrofolate Reductase (NADPH2); D013766:5-Methyltetrahydrofolate-Homocysteine S-Methyltransferase