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Dopamine transporter gene (DAT1) associated with appetite suppression to methylphenidate in a case-control study of binge eating disorder

Department of Kinesiology and Health Sciences, York University, Toronto, ON, Canada.
Neuropsychopharmacology (Impact Factor: 7.83). 11/2007; 32(10):2199-206. DOI: 10.1038/sj.npp.1301348
Source: PubMed

ABSTRACT Response to psychomotor stimulants is highly variable across individuals. Such inconsistencies are influenced by many factors including drug dose and polymorphic differences in genes that encode proteins, such as the dopamine transporter (DAT1), which are relevant to the site of action of these substances. The current study used a double blind, crossover (methylphenidate vs placebo) design to assess DAT1 genotype differences on appetite ratings to a snack-food cue in subjects with binge eating disorder (BED) (n=32) and healthy age-matched controls (n=46). ANOVA results indicated a significant genotype x diagnostic group interaction whereby BED subjects with at least one copy of the 9-repeat allele showed a significant suppression of appetite in response to methylphenidate compared with controls with this allele, or to subjects with the 10/10 genotype (irrespective of diagnosis) whose drug response was indistinguishable from placebo. The most probable explanation for these findings is that some, currently unknown, genetic variant, which is overrepresented in those with BED, interacts with DAT1 to suppress appetite in response to stimulant administration. The current findings have implications for treatment response to drugs currently in use (or being developed) for the treatment of overeating and overweight.

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Available from: Caroline Davis, Feb 03, 2015
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    • "Individuals vary in their therapeutic and acute behavioral responses to stimulant drugs. This variability has been observed in clinical populations, such as patients treated for Binge Eating Disorder (Davis et al. 2007), Attention- Deficit Hyperactivity Disorder (Spencer et al. 1996) and narcolepsy (Mitler et al. 1993). Variability has also been reported in healthy volunteers, who receive acute doses of stimulants in laboratory studies (Brauer and de Wit 1996; Lott et al. 2005; de Wit et al. 1986; Gabbay 2003). "
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