O-Glycan sialylation of skeletal muscle specimens from DMRV patients and controls. The sialic acid contents of skeletal muscle specimens from DMRV patients (n = 4; DMRV-2, DMRV-4, DMRV-5B, and DMRV-5S-1) and controls (n = 3) were determined by the fluorometric HPLC method. Glycoproteins in skeletal muscle homogenates treated with N-glycosidase F were subjected to SDS-PAGE, followed by blotting onto a PVDF membrane, as described in Materials and Methods. The membrane was cut into eight equal pieces according to Mr. Each column represents the means ± SD. *, P < 0.05.