Moreover, administration of 5-HT7 antagonists in adolescent rats has been shown to enhance behavioral impulsivity, while agonist-induced activation of endogenous 5-HT7 significantly increased neurite length in striatal neuron primary cultures, suggesting remodeling of neuronal plasticity in brain reward circuits [Leo et al., 2009]. However, previous studies on human brain oscillation measures and alcohol dependence have not found any evidence of genetic association involving serotonin receptors. However, in a pair of recent genome-wide linkage studies, a significant linkage peak (LOD = 3.3) was identified at chromosome 10q23.3 – 10q24.1 for alcohol dependence in African-Americans [Gelernter et al., 2009], as well as a suggestive signal (LOD = 2.6) at 10q23.1 – 10q25.1 for a quantitative measure of alcoholism and illicit drug dependence [Agrawal et al., 2008], a region that encompasses the HTR7 gene.
