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LINKS: ....Bird Flu Info ....Your Memory Enhancer ....Neurotech ....Success Tips ....Free Reward Genes and The Addictive BrainIn 1990 Kenneth Blum in conjunction with Ernest P. Noble from UCLA and our colleagues, published a paper (Blum et al. 1990) suggesting that a specific genetic anomaly was linked to alcoholism. Unfortunately it often was reported erroneously that we had found the "alcoholism gene." Such misinterpretations are common-readers may recall accounts of an "obesity gene" or a "crime gene." These reports imply that there is a one-to-one relationship between a gene and a specific behavior. Needless to say, there is no such thing as a specific gene for alcoholism, obesity, or criminal behavior. However, it would be naive to assert the opposite, that these complex problems of human behavior are not associated with any particular genes. Rather the issue at hand is to understand how certain genes and behaviors are connected. In the past nine years scientists have pursued the association between certain genes and various behavioral disorders. In molecular genetics, an association refers to a statistically significant incidence of a genetic variant (an allele) among genetically unrelated individuals with a particular disease or condition compared to a control population. In the course of our work Blum and others discovered that the genetic anomaly previously found to be associated with alcoholism also is found among people with other addictive, compulsive, or impulsive disorders. The list is long and remarkable-it comprises overeating and obesity, Tourette's Syndrome, attention deficit disorder and pathological gambling. We believe these disorders are linked by a common biological substrate, a "hard-wired" system in the brain (consisting of cells and signaling molecules) that provides pleasure in the process of rewarding certain behavior. Consider how people respond positively to safety, warmth and a full stomach. If these needs are threatened or are not being met, we experience discomfort and anxiety. An inborn chemical imbalance that alters the intercellular signaling in the brain's reward process could supplant an individual's feeling of well - being with anxiety, anger or a craving for a substance that can alleviate the negative emotions. This chemical imbalance manifests itself as one or more behavioral disorders termed "Reward Deficiency Syndrome." This syndrome involves a form of sensory deprivation of the brain's pleasure mechanisms. It can be manifested in relatively mild or severe forms that follow as a consequence of an individual's biochemical inability to derive reward from ordinary, everyday activities. We believe that we have discovered at least one genetic aberration that leads to an alteration in the reward pathways of the brain. It is a variant form of the gene for the dopamine D2 receptor, called the A1 allele (low D2 receptors), which may have been the natural prehistoric trait. This is the same genetic variant we previously found to be associated with alcoholism (Blum, et al. 1990) as well as obesity (see below). In this position paper we look at evidence suggesting the A1 allele also is associated with a spectrum of impulsive, compulsive, and addictive behaviors, including a predisposition to overeating. The concept of the Reward Deficiency Syndrome unites these impul-sive/addictive/compulsive behaviors and may explain how simple genetic anomalies give rise to complex aberrant behavior. Oddly enough, compared to the so called "normal?variant the A2, which occurs in approximately one-third of Americans having a normal compliment of D2 receptors, the A1 carriers may be predisposed to overeating, have a higher percent body fat, and have innate craving for carbohydrates. HOME...... Brain Food LINKS: ....Medical Dictionary ....Stress Management ....Allergy Info |