Although we observed co-localization of the antisense foci with MBNL1 in human DM1 heart, we did not see clear co-localization with MBNL1 or MBNL2 in DMSXL heart and skeletal muscles, probably due to the low levels of antisense transcripts in the transgenic mice. The gene discussed is MBNL1; the disease is myotonic dystrophy type 1.