Progressive Diseases: AMD and ALS

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Hi,
Below I have explained in details the two progressive diseases Duchenne muscular dystrophy (DMD) & AMYOTROPHIC LATERAL SCLEROSIS (ALS). Please go through the MS word attachment which has some additional figures. Lot of information is provided here, I believe you can fish-out the relevant information from here.

Duchenne muscular dystrophy (DMD)
INTRODUCTION:

Dystroglycan complex (DGC) is a protein complex that connects cytoskeleton of muscle fiber to the surrounding extracellular matrix via the cell membrane. The rod-shaped protein Dystrophin forms an integral part of this DGC complex. Duchenne muscular dystrophy (DMD) is a genetic disease characterized by progressive muscle degeneration and weakness where individuals are unable to synthesize the protein dystrophin, which leads to disruption of muscle stability.

**Reference: fishingformd.blogspot.com

While both sexes can carry the mutation, females rarely exhibit signs of the disease.
Symptom onset is in early childhood, usually between ages 3 and 5. The disease primarily affects boys, but in rare cases it can affect girls.

SYMPTOMS:
EARLY AGE SYMPTOM:
Males in ages as early as ~2-3 years get affected by DMD. Laboratory genetic testing can identify the mutation of the Dystrophin gene even in infant males. Legs and pelvis showing progressive muscle weakness followed by reducing muscle mass are the first symptoms observed. Eventually this weakness spreads to the arms, neck, and other areas.

LATER AGE SYMPTOM:
Gradually as one becomes older muscle fibrosis is observed and by the age 10 braces may be required to aid in walking but most patients are wheelchair dependent by age 12. Curvature of spine is also observed in the later ages in some individuals. Paralysis later sets in resulting in total loss of movement. The average life expectancy for individuals afflicted with DMD is around 25.

CAUSES:

The short arm of the female X chromosome (Xp21) harbors the Dystrophin gene. This is a recessive gene, which means when present with a X chromosome with a normal Dystrophin gene, the symptoms of the disease are not shown.

The figure here shows the inheritance pattern in DMD disorder. Off-springs originating from a normal father and carrier mother can result in male child with 50% chance of developing the disease and female child with 50% chance of being a carrier. Absence of dystrophin results in bursting of muscle cells due to high level of reactive oxygen species (ROS) and calcium influx resulting in muscle fibrosis and degeneration.
Duchenne muscular dystrophy has an incidence of 1 in 3,600 male infants.

TREATMENTS:
There are no cures for DMD. Following are the treatments available which can alleviate the condition of the patient:

Current therapies:
• Physical therapy: These therapies help patient reach their maximum physical potentials to stretch and use their muscles to the fullest extent possible in ...