Common Leptin Receptor Polymorphisms do not Modify the Effect of Alcohol Ingestion on Serum Leptin Levels in a Controlled Feeding and Alcohol Ingestion Study

Nutritional Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, Suite 705, MSC 8314, Bethesda, Maryland 20892, USA.
Cancer Epidemiology Biomarkers & Prevention (Impact Factor: 4.13). 07/2005; 14(6):1576-8. DOI: 10.1158/1055-9965.EPI-05-0008
Source: PubMed


We explored whether serum leptin response to alcohol ingestion was related to common leptin receptor gene polymorphisms, K109R (Lys109Arg), Q223R (Gln223Arg), S343S [Ser(T)343Ser(C)], and K656N (Lys656Asn), of reported physiologic significance during a controlled intervention. Fifty-three participants rotated through three 8-week treatment periods and consumed 0, 15 (equivalent to one drink), or 30 g (equivalent to two drinks) of alcohol (95% ethanol in 12 ounces of orange juice) per day, in random order. During the controlled feeding periods, all food and beverages including alcoholic beverages were prepared and supplied by the staff of the Beltsville Human Nutrition Research Center's Human Study Facility (Beltsville, MD), and energy intake was adjusted to maintain a constant weight. Blood was collected after an overnight fast on 3 separate days during the last week of each controlled feeding period and pooled for hormone analysis. Circulating serum leptin concentration was measured in duplicate by RIA and genotype analysis was done on DNA extracted from WBC using real-time PCR analysis amplification (TaqMan). Linear mixed models with a single random intercept reflecting a participant effect were used to estimate changes in serum leptin levels at 15 and 30 g of alcohol per day relative to 0 g of alcohol per day. No significant effects were found between common leptin receptor polymorphisms and serum leptin levels (P > or = 0.26).

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