Table 1.
Clinical features and dystrophin gene mutation in Becker muscular dystrophy (BMD) patients.
| Age at Study (Years) | Age at Onset (Years) | Deletion in the Dystrophin Gene | Dystrophin Quantity (%) and M.W. (kDa) * | Creatine Kinase Levels (U/L) | Muscle Involvement |
Left Ventricular Ejection Fraction ** | Treatment and Duration | |
|---|---|---|---|---|---|---|---|---|
| Patient 1 | 42 | 5 | Exons 45–47 | 35%, 370 kDa |
1202 | HyperCKemia, waddling gait, calf hypertrophy, quadriceps weakness | 40–55% | Deflazacort ACE inhibitors 26 years |
| Patient 2 | 40 | 17 | Exons 45–49 | 60%, 380 kDa |
452 | HyperCKemia, pes cavus, difficulty rising from the floor, calf atrophy, weakness | 55% | Deflazacort 20 years |
| Patient 3 | 33 | 1 1/2 | Exons 48–51 | 90%, 370 kDa |
189 | Slight hyperCKemia, muscle cramps, quadriceps weakness | 65% | No |
| Patient 4 | 41 | 6 | Exons 31–44 | 35%, 320 kDa |
3086 | HyperCKemia, mild mitral valve insufficiency | 55% | No |
| Patient 5 | 17 | 6 | Exons 45–47 | 20%, 380 kDa |
1092 | HyperCKemia, calf hypertrophy | 64% | No |
| Patient 6 | 14 | 3 | Exons 45–51 | 50%, 370 kDa |
668 | HyperCKemia, mild winging scapulae | 65% | No |
| Patient 7 | 30 | 1 1/2 | Exons 48–49 | 50%, 380 kDa |
1305 | HyperCKemia, slight scoliosis, calf hypertrophy | 55% | No |
| Patient 8 | 45 | Childhood | Exons 47–49 | N.A. | 597–943 | HyperCKemia, slight scapular winging, calf hypertrophy | 55% | No |
N.A.: not available. *: dystrophin quantity was expressed as percentage of control mean; dystrophin molecular weight (M.W.) was measured by comparison with those on normal muscle (400 kDa) as determined by Western blotting on muscle biopsy tissue obtained at the time at diagnosis. **: normal values 53–63%.