But what the research does show is the first strong connection in brain tissue between the mutations and the presence of severe cocaine abuse.
"We now have both good biological rationale and clinical association showing that this has an impact on the way cocaine abuse might progress or might be initiated," said Wolfgang Sadee, professor of pharmacology and director of the Program in Pharmacogenomics at Ohio State and senior author of the study. "We have found a frequent variant in one of the key candidate genes that can affect cocaine abuse, but more importantly, it also opens the avenue to explore how this variant affects response to therapies for a variety of psychiatric disorders that involve dopamine."
The research appears online and is scheduled for later print publication in the journal Neuropsychopharmacology.
The mutations described in this study are single-nucleotide polymorphisms, or SNPs (pronounced "snips"). Each gene contains two alternative forms called alleles that are identical in most people. However, in some cases, the activity level, or expression, of an allele can differ from its partner allele in a single gene. Each small difference is a SNP.
SNPs have become the primary study target of Ohio State's Program in Pharmacogenomics. But the mutations Sadee studies aren't just any SNPs. Up until about 10 years ago, most biological research focused on these tiny mutations in areas of genes that produce proteins. But Sadee's lab explores the role of SNPs that are present earlier in a gene's existence, located in regions called introns.
A better understanding of the human genome has led scientists to determine that about 90 percent of the mutations that can lead to disease or govern behavior actually are located in these deeper and often overlooked regions of genes, and that they regulate
|Contact: Wolfgang Sadee|
Ohio State University