Typical of the revertant fiber transcripts reported to be present in at least 50% of DMD patients (Sherratt et al. 1993; Winnard et al. 1993), this particular transcript is in-frame but occurs at a very low frequency, demonstrated by the sporadic detection at the RNA level and absence of dystrophin on a western blot. This evidence concerns the gene DMD and Duchenne muscular dystrophy.