mNSC1 shows no evidence of protein-coding capacity

The Mus musculus non-selective cation channel gene mNSC1 was used as a classical example of a gene derived from transposable elements. To study the evolution of mNSC1 in M. musculus we sequenced this locus in M. musculus, M. hortulanus, M. spretus, M. caroli, and M. pahari. We found that the previously published 1,275 bp coding region was not present in any of these species. We identified a second possible coding region that was present only in M. musculus. However, RT-PCR experiments did not confirm the expression of the second reading frame. Our findings suggest that mNSC1 lacks protein-coding capacity and highlight the need for comparative validation of all TE-containing genes.