Genetics

In a surprising finding, male rats who used cocaine sired male offspring who later exhibited blunted responses to the drug. Researchers determined the cause was an epigenetic alteration.

NIDA-supported research suggests that glucocorticoid receptor levels during early brain development affect the hard wiring of neural circuits that shape an individual’s basic emotional makeup. In mice, overexpression of the glucocorticoid gene in the first weeks after birth increased anxiety and response to cocaine in adulthood. These findings may help researchers understand the genetic background and the developmental trajectory of addiction.

NIDA researchers working with human subjects now have a new resource at their fingertips: the PhenX Toolkit’s new Substance Abuse and Addiction (SAA) Collection. The Toolkit is designed to provide standardized measures, vetted and approved by the field, to help researchers compare and combine data from multiple studies.

Dr. J. David Jentsch is the recipient of the 2011 Jacob P. Waletzky Memorial Award for Innovative Research in Drug Addiction and Alcoholism. Dr. Jentsch and colleagues at the University of California, Los Angeles, are studying genetic and neurochemical factors that influence individual differences in inhibitory control.

Reports on the relative influence of genes versus environment on adolescents’ choices that involve delayed gratification.

Individuals with weak signaling in a nicotine-sensitive brain circuit were more vulnerable to nicotine dependence than those with stronger signaling, according to a study conducted while the subjects’ brains were in a resting state. A second resting-state study finds that the same circuit appears to mediate dependence associated with a genetic risk factor for smoking.

Reports on the research underway to identify gene variations associated with nicotine addiction and the interaction of genetic makeup, experiences, and surroundings to addiction.

Describes a study showing that cocaine, which increases dopamine levels, also can tap into an intracellular dopamine reserve pool.

Discusses the role of epigenetics, the study of cellular mechanisms that control gene expression and its impacts on health and behavior, in addiction research.

Describes the work of researchers who have found a statistical link between one region on chromosome 17 and an increased risk of opioid dependence.