We aimed to locate a chronic pain-associated QTL in the rat (Rattus norvegicus) based on previous findings of a QTL (pain1) on chromosome 15 of the mouse (Mus musculus). The work was based on rat selection lines HA (high autotomy) and LA (low autotomy) which show a contrasting pain phenotype in response to nerve injury in the neuroma model of neuropathic pain. An F2 segregating population was generated from HA and LA animals. Phenotyped F2 rats were genotyped on chromosome 7 and chromosome 2, regions that share a partial homology with mouse chromosome 15. Our interval mapping analysis revealed a LOD score value of 3.63 (corresponding to p = 0.005 after correcting for multiple testing using permutations) on rat chromosome 2, which is suggestive of the presence of a QTL affecting the predisposition to neuropathic pain. This QTL was mapped to the 14-26 cM interval of chromosome 2. Interestingly, this region is syntenic to mouse chromosome 13, rather than to the region of mouse chromosome 15 that contains pain1. This chromosomal position indicates that it is possibly a new QTL, and hence we name it pain2. Further work is needed to replicate and to uncover the underlying gene(s) in both species.
Bibliographical noteFunding Information:
We thank Mira Korner and Nissim Ben-Arieh for their assistance and advice. This work was supported by the Israeli Ministry of Science and Technology, the Israel Science Foundation (ISF), the Hebrew University Center for Research on Pain, and the European Community’s 6th Framework Program (project LSHM-CT-2004-502800 PainGenes). The manuscript reflects only the author’s views. The European Community is not liable for any use that may be made of the information contained therein.
- Neuroma model
- Neuropathic pain
- Pain QTL