D2 dopamine receptor Taq1A polymorphism, body weight, and dietary intake in type 2 diabetes

Department of Medicine, George Washington University School of Medicine, Washington, D.C., USA.
Nutrition (Impact Factor: 2.93). 10/2008; 25(1):58-65. DOI: 10.1016/j.nut.2008.07.012
Source: PubMed


Certain D2 dopamine receptor Taq 1A genotypes (A1A1, A1A2) have been associated with obesity and substance abuse. We hypothesized that their presence would be associated with reduced efficacy of dietary interventions in individuals with type 2 diabetes.
In the course of a randomized clinical trial in an outpatient research center in which 93 adults with type 2 diabetes were assigned to a low-fat vegan diet or a diet following 2003 American Diabetes Association guidelines for 74 wk, Taq 1A genotype was determined. Nutrient intake, body weight, and hemoglobin A1c (A1c) were measured over 74 wk.
The A1 allele was highly prevalent, occurring in 47% of white participants (n = 49), which was significantly higher than the 29% prevalence previously reported in non-diabetic whites (P = 0.01). The A1 allele was found in 55% of black participants (n = 44). Black participants with A1(+) genotypes had significantly greater mean body weight (11.2 kg heavier, P = 0.05) and greater intake of fat (P = 0.002), saturated fat (P = 0.01), and cholesterol (P = 0.02) compared with A2A2 (A1(-)) individuals; dietary changes during the study did not favor one genotype group. Among whites, baseline anthropometric and nutrient differences between gene groups were small. However, among whites in the vegan group, A1(+) individuals reduced fat intake (P = 0.04) and A1c (P = 0.01) significantly less than did A1(-) individuals.
The A1 allele appears to be highly prevalent among individuals with type 2 diabetes. Potential influences on diet, weight, and glycemic control merit further exploration.

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Available from: Gabrielle Turner-McGrievy
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    • "Since that time there have been no less than 3738 (Pubmed-6-23-14) peer reviewed articles on many peripheral and central nervous system (CNS) behaviors and physiological processes. Understandably addiction or even the broader term RDS involves very complex gene × environment interaction and one cannot expect that a single gene like the DRD2 gene would have a powerful effect by itself, however, albeit many negative findings, there is still a plethora of evidence for the role of the DRD2 gene polymorphisms and a number (small sample of studies represented herein) of addictive and other reward dependent behaviors including: alcohol dependence (Pato et al., 1993; Ponce et al., 2003; Munafò et al., 2007; Smith et al., 2008; Pinto et al., 2009; Grzywacz et al., 2012; Wang et al., 2013); drug dependence (Li et al., 2004; Xu et al., 2004; Young et al., 2004; Barratt et al., 2006; Li et al., 2006; Hou and Li, 2009; Chen et al., 2011a,b; Al-Eitan et al., 2012; Jacobs et al., 2013; Lee et al., 2013; Ohmoto et al., 2013; Sullivan et al., 2013; Suraj Singh et al., 2013; Vereczkei et al., 2013; Wang et al., 2013; Clarke et al., 2014; Roussotte et al., 2014; Schuck et al., 2014); mood disorders (Vaske et al., 2009; Huertas et al., 2010; Zhu et al., 2011; Zou et al., 2012; Hettinger et al., 2012; Jutras-Aswad et al., 2012; Tsuchimine et al., 2012; Whitmer and Gotlib, 2012; Zai et al., 2012; Peciña et al., 2013; Zhang et al., 2014); rearing behaviors (Mills-Koonce et al., 2007; Bakermans-Kranenburg and van Ijzendoorn, 2011; Beaver and Belsky, 2012; Masarik et al., 2014); obesity (Spangler et al., 2004; Fang et al., 2005; Huang et al., 2005; Epstein et al., 2007; Nisoli et al., 2007; Barnard et al., 2008; Blum et al., 2008; Eny et al., 2009; Epstein et al., 2010; Mathes et al., 2010; Stice et al., 2010; van Strien et al., 2010; Jabłoński, 2011; Anitha et al., 2012; Chen et al., 2012; Winkler et al., 2012; Ariza et al., 2013; Carpenter et al., 2013; Cameron et al., 2013; Hess et al., 2013; Alsiö et al., 2014); Anorexia Nervosa (Bergen et al., 2005); motivation (Trifilieff et al., 2013); brain metabolism (Noble et al., 1997); ADHD (Gold et al., 2014), and pathological gambling (Gyollai et al., 2014). "
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    • "Additionally, dopamine plays a key role in the central regulation of insulin action: bromocriptine, a DRD2 agonist, significantly reduces HbA1c and fasting plasma glucose in individuals with type 2 diabetes (Pijl et al., 2000). Barnard et al. (2009) found that, the A1 + genotypes were highly prevalent among type 2 diabetic patients. In this study, Taq1A1/A1 genotye of the DRD2 gene was associated with hyperinsulinemia in adolescent obese subjects. "
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