1. Becker Muscular Dystrophy (BMD) is a muscular dystrophy that involves a mutation in Dystrophin.
2. How do the length of the H and I bands of the sarcomere change in muscle contraction?
3. Pseudohypertrophy is a feature of Duchenne Muscular Dystrophy that typically presents at the calf muscles due to fibrofatty replacement of muscle.
4. What gene undergoes a frameshift mutation in Duchenne Muscular Dystrophy?
Dystrophin; mutation truncates the proteins; results in accelerated muscle breakdown. Hence, the loss of dystrophin in Duchenne Muscular Dystrophy results in myonecrosis
5. Type 1 muscle fibers are a type of muscle fiber that perform sustained contraction due to an increased concentration of mitochondria and myoglobin (i.e. increased oxidative phosphorylation capacity).
Hence these fibers are “red” fibers.
6. Which gene is mutated in Becker Muscular Dystrophy?
DMD = frameshift mutation in Dystrophin causing deletion of the protein
BMD = point mutation in Dystrophin, hence less severe
Both BMD and DMD = X-linked recessive
7. What type of mutation is seen in Duchenne Muscular Dystrophy?
Frameshift mutation – Causes a truncated Dystrophin protein and accelerated muscle breakdown
8. Where in the body does muscle weakness first appear in Duchenne Muscular Dystrophy?
9. How do Aldolase levels change in Duchenne Muscular Dystrophy?
10. What is the genetic inheritance of Duchenne’s Muscular Dystrophy (DMD)?
11. The Gower maneuver is a feature of Duchenne Muscular Dystrophy that involves patients using their upper extremities to help them stand up. These patients are typically young (< 5 y/o) and male (X-linked recessive).
12. How do CK-MM (Creatine Kinase) levels change in Duchenne Muscular Dystrophy?
13. What cardiac complications are seen in Myotonic Muscular Dystrophy Type 1?
14. Which human gene has the longest coding region?
Dystrophin (DMD) – For this reason there is an increased risk of spontaneous mutation
15. Which type of muscle fibers are referred to as slow twitch fibers?
16. Which type of muscle fibers typically yield hypertrophy as a result of weight training?
Type 2, fast-twitch, white muscle fibers
17. What is the typical lifespan of someone with Becker Muscular Dystrophy?
18. What is the genetic inheritance of Becker Muscular Dystrophy?
19. What type of mutation is seen in Becker Muscular Dystrophy?
20. Troponin C is a protein in muscle that binds to Ca2+ and causes a conformational change that moves tropomyosin out of the myosin-binding site on actin filaments.