Genetic mapping in collaborative cross mouse strains identifies loci that affect initial sensitivity to cocaine

Area of Science:

• Neuroscience
• Genetics
• Pharmacology

Background:

• Cocaine use disorder (CUD) poses a major public health challenge with limited treatment options.
• Genetic factors significantly contribute to an individual's susceptibility to CUD.
• Understanding genetic risk mechanisms is crucial for developing novel CUD therapies.

Purpose of the Study:

• To identify genetic loci associated with behavioral responses to cocaine.
• To leverage distinct Collaborative Cross (CC) mouse strains with differing cocaine responses for genetic mapping.

Main Methods:

• Cross-breeding of high-responding (CC004) and low-responding (CC041) mouse strains with C57BL/6NJ mice to create F2 mapping populations.
• Analysis of locomotor response to cocaine in F2 populations.
• Bioinformatic analysis to identify candidate genes within significant genetic loci.

Main Results:

• Three significant genetic loci on chromosomes 7, 11, and 14 were identified in the CC041 F2 cross, explaining 14% of variance in cocaine-induced locomotor response.
• Multiple plausible candidate genes with functional relevance were pinpointed on chromosomes 7 and 11.
• This study demonstrates the utility of genetically divergent mouse models in dissecting complex behaviors.

Conclusions:

• Genetically distinct mouse strains are valuable for discovering genes influencing psychostimulant responses.
• Further investigation of identified genes can illuminate biological pathways underlying CUD risk.
• This research provides a foundation for developing targeted CUD prevention and treatment strategies.