A recent study has found the genetic markers that influence addiction, in rats. It's the first time scientists have shown in selectively bred animals that the propensity for addiction is linked to differences in expression of genes for specific molecules in a specific brain region.

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A recent study has found the genetic markers that influence addiction, in rats. It's the first time scientists have shown in selectively bred animals that the propensity for addiction is linked to differences in expression of genes for specific molecules in a specific brain region.