Preliminary studies of its expression in DMD muscle biopsies were attached to the report of CD40 as a DMD modifier [66] (at diagnosis, priori to GC treatment), which surprisingly showed increased levels of CD40 transcript, assessed by RT-PCR, in association with the T allele (n = 16, p = 0.005), but expectedly, reduced levels of CD40 protein with the same allele (n = 6, p = n.s.). Here, CD40 is linked to Duchenne muscular dystrophy.