Analysis of candidate genes for morphine preference quantitative trait locus Mop2.
G A Doyle1, C L Schwebel1, S E Ruiz1
1Center for Neurobiology and Behavior, Department of Psychiatry, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA.
Neuroscience
|July 25, 2014
Summary
Researchers identified genetic factors influencing morphine preference in mice. By narrowing down a key region on chromosome 10, they pinpointed several genes, including Oprm1, potentially contributing to this behavior in C57BL/6J and DBA/2J strains.
Area of Science:
- Genetics
- Neuroscience
- Pharmacology
Background:
- C57BL/6J (B6) mice show a stronger morphine preference than DBA/2J (D2) mice.
- A quantitative trait locus (QTL) for morphine preference, Mop2, was previously mapped to mouse chromosome 10.
Purpose of the Study:
- To fine-map the Mop2 QTL to a smaller genetic interval.
- To identify candidate genes responsible for morphine preference differences between B6 and D2 mice.
Main Methods:
- Utilized a two-bottle choice drinking paradigm to assess morphine preference.
- Generated and tested congenic and recombinant inbred mouse strains.
- Performed quantitative real-time PCR (qRT-PCR) and Western blot analysis for gene and protein expression.
Main Results:
- Reduced the Mop2 QTL interval to approximately 7.6 Mbp, containing 22 genes including Oprm1.
- Observed significant differences in Oprm1, Rgs17, Ppp1r14c, Vip, and Iyd gene expression between B6 and D2 mice.
- Detected variations in Rgs17 protein levels between and within the mouse strains.
Conclusions:
- The Mop2 QTL likely involves multiple genetic variants influencing morphine preference.
- Oprm1 and other opioid-related genes are potential contributors to the observed strain differences in morphine preference.
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