Lysosomal Storage Diseases

There are 40 known lysosomal storage diseases.
There may be 47 enzymes associated with these diseases, but mutations haven't been found for all of them. Possible reasons include:
- Some mutations may be embryonic lethal.
- Some enzymes may have overlapping functions, so if one is mutated, another can compensate.

Skeletal deformities
Muscle weakness
In nervous system-related diseases (e.g., Tay Sachs), mental retardation
Often fatal due to accumulation of substances in cells, impairing their function.

Mutation in the alpha 14 glucosidase enzyme.
Alpha 14 glucosidase breaks down glycogen.
Glycogen is typically found in the cytoplasm but can enter the lysosomes.
Common in cells where glycogen is stored:
- Liver: Glycogen stored in the liver is used to maintain glucose levels for the entire body.
- Muscle: Glycogen stored in the muscle is used only by the muscle.
- Brain: Glycogen stored in the brain is used only by the brain.
Death usually occurs within nine months of birth, depending on the severity of the mutation:
- If the protein has no function, death occurs early.
- If the protein has a little function, the individual may live longer.

Mutation in the beta N acetylhexosaminidase enzyme.
Beta N acetylhexosaminidase breaks down gangliosides.
Without the enzyme, gangliosides accumulate in lysosomes, causing them to enlarge.
Bulging lysosomes interfere with cell function.
Symptoms:
- Mental deterioration starting at six months old.
- Paralysis.
- Death usually within three years.
These issues disrupt the cell's ability to function properly.