Lysosomal Storage Disorders Support Society

What are Lysosomal Storage Disorders (LSDs)?

Lysosomal storage Disorders (LSDs) are a group of approximately 45 rare genetic disorder caused by deficiency of certain enzymes in certain compartments of the cells. All LSDs share a common pathogenesis: a genetic defect in one or more specific lysosomal enzymes, activator protein or membrane protein, resulting in deficient enzymatic activity. In other words, when the lysosome does not function normally, excess products destined for breakdown and recycling is stored in the cell.

The lysosome itself was discovered in 1955 and by 1960 its role in cellular digestion was well understood. Pompe disease was the first to be formally diagnosed. By 1970s the scientific community had recognized many more LSDs and categorized them based on the type of enzymatic defect and/or stored substrate product.

The symptoms of Lysosomal Storage Disease vary, depending on the particular disorder and other variables like the age of onset, and can be mild to severe. They can include developmental delay, movement disorders, seizures, dementia, deafness and/or blindness. Some people with Lysosomal Storage Disease have enlarged livers (hepatomegaly) and enlarged spleens (splenomegaly), pulmonary and cardiac problems, and bones that grow abnormally.

A patient with LSD not only develops physical deformation in cell structures throughout the body, but these cells often die resulting in a wide variety of clinical symptoms. If diagnosed late and/or left untreated patients are at risk of developing significant, irreversible damage and loss of body functions, and life-threatening complications.

LSDs encompass a broad group of rare, inherited metabolic conditions resulting from defects in lysosomal function. Here’s a comprehensive
list of known LSDs:

Glycogen Storage Diseases

  1. Pompe Disease (Glycogen Storage Disease Type II)



  1. Gaucher Disease
  2. Fabry Disease
  3. Niemann-Pick Disease Types A and B (SMPD1-related)
  4. Niemann-Pick Disease Type C (NPC1 and NPC2-related)
  5. Tay-Sachs Disease
  6. Sandhoff Disease
  7. Metachromatic Leukodystrophy (MLD)
  8. Krabbe Disease (Globoid Cell Leukodystrophy)
  9. Farber Disease
  10. GM1 Gangliosidosis
  11. GM2 Gangliosidosis (Tay-Sachs and Sandhoff Diseases)
  12. Schindler Disease
  13. Fabry-Anderson Disease


Mucopolysaccharidoses (MPS)

  1. MPS I (Hurler, Scheie, and Hurler-Scheie Syndromes)
  2. MPS II (Hunter Syndrome)
  3. MPS III (Sanfilippo Syndrome, Types A, B, C, D)
  4. MPS IV (Morquio Syndrome, Types A and B)
  5. MPS VI (Maroteaux-Lamy Syndrome)
  6. MPS VII (Sly Syndrome)
  7. MPS IX (Hyaluronidase Deficiency)


  1. Aspartylglucosaminuria
  2. Fucosidosis
  3. Mannosidosis (Alpha and Beta)
  4. Sialidosis
  5. Schindler Disease
  6. Galactosialidosis



  1. Alpha-Mannosidosis
  2. Beta-Mannosidosis
  3. Aspartylglucosaminuria
  4. Fucosidosis
  5. Sialidosis
  6. Galactosialidosis
  7. Mucolipidosis II (I-Cell Disease)
  8. Mucolipidosis III (Pseudo-Hurler Polydystrophy)


  1. Wolman Disease
  2. Cholesteryl Ester Storage Disease
  3. Farber Lipogranulomatosis


Neuronal Ceroid Lipofuscinoses (NCL)

  1. Infantile NCL (CLN1/PPT1)
  2. Late Infantile NCL (CLN2/TPP1)
  3. Juvenile NCL (CLN3)
  4. Adult NCL (CLN4/Kufs)
  5. CLN5 Disease
  6. CLN6 Disease
  7. CLN7 Disease
  8. CLN8 Disease
  9. CLN10 Disease (CTSD)
  10. CLN11 Disease (GRN)



  1. Mucolipidosis II (I-Cell Disease)
  2. Mucolipidosis III (Pseudo-Hurler Polydystrophy)
  3. Mucolipidosis IV


Cystine Storage Diseases

  1. Cystinosis


Sialic Acid Storage Diseases

  1. Salla Disease
  2. Infantile Free Sialic Acid Storage Disease


Other LSDs

  1. Multiple Sulfatase Deficiency (Austin Disease)
  2. Danon Disease (LAMP2 Deficiency)
  3. Pycnodysostosis
  4. Hereditary Inclusion Body Myopathy 2 (GNE Myopathy)
  5. Niemann-Pick Disease, Type D

This list includes many of the known LSDs, but the field of Lysosomal Storage Disorders is continually evolving as new conditions are
identified and better understood.


There are no cures for lysosomal storage diseases and treatment is mostly symptomatic, although bone marrow transplantation and enzyme replacement therapy (ERT) have been successful in some cases.  In addition, umbilical cord blood transplantation is being performed at specialized centers for a number of these diseases. In addition, substrate reduction therapy, a method used to decrease the accumulation of storage material, is currently being evaluated for some of these diseases. Furthermore, chaperone therapy, a technique used to stabilize the defective enzymes produced by patients, is being examined for certain of these disorders. Gene therapy involves replacing the patient’s mutated gene with a normal copy to allow proper enzyme production. However, it is still in the pre-clinical phase (animal studies) and much research is needed.


The majority of the patients are initially screened by enzyme assay, which is the most efficient method to arrive at a definitive diagnosis. In some families where the disease-causing mutation(s) is known and in certain genetic isolates, mutation analysis may be performed. In addition, after a diagnosis is made by biochemical means, mutation analysis may be performed for certain disorders.

Most Common LSDs in India

Following are the most common types of Lysosomal Storage Disorders found in India. To know more about each of these disorders, click on any disease name below.


Gaucher Disease

Gaucher disease is a rare genetic disorder caused by the deficiency of an enzyme wherein fat-laden Gaucher cells build up in areas like the spleen, liver and bone marrow, typically causing an enlarged abdomen.

pompe disease

Pompe Disease

Pompe disease is a genetic disorder in which complex sugar called glycogen builds up in the body's cells. This disease is caused by the deficiency of acid alfa glucosidase (GAA) enzyme.


Fabry Disease

The genetic mutation that causes Fabry disease interferes with the function of an enzyme that processes biomolecules known as sphingolipids, leading to these substances building up in the walls of blood vessels and other organs.

lysosomal storage disorder


In individuals with MPS, a deficiency or malfunction of specific enzymes leads to an abnormal accumulation of certain complex carbohydrates in the arteries, skeleton, eyes, joints, ears, skin, and/or teeth.