Niemann-Pick Disease

About Niemann-Pick Disease: 

• It is a rare genetic disorder in which sphingomyelin accumulates in lysosomes inside cells.
• This disease involves dysfunctional metabolism of sphingolipids.
• The three most commonly recognized forms are Niemann-Pick Types A and B and Type C.
• This disease can affect the brain, nerves, liver, spleen, bone marrow and, in severe cases, lungs.
• People with this condition experience symptoms related to progressive loss of function of nerves, the brain and other organs.
• It can occur at any age but mainly affects children.
• Causes:
  • It is inherited in an c pattern, which means both copies of the gene must be defective to cause the disease.
  • Most often, the parents of a child with an autosomal recessive disorder are carriers: they have one copy of the altered gene, but are not affected because the other copy produces the enzyme.
  • If both parents are carriers, each pregnancy has a 25% chance of producing an affected child.
• Symptoms
  • Enlargement of the liver and spleen (Hepatosplenomegaly)
  • Low levels of platelets in the blood(Thrombocytopenia)
  • Slurring of speech (dysarthria)
  • Difficulty in swallowing (dysphagia)
  • Abnormal posturing of the limbs, trunk, and face (dystonia).
  • Voluntary rapid eye movements (supranuclear gaze palsy).
  • Gradual loss of intellectual abilities, causing dementia and seizures
  • Classification
  • Types A and B: Mutations in the SMPD1 Gene cause types A and B.
  • They produce a deficiency in the activity of the lysosomal enzyme acid sphingomyelinase that breaks down the lipid sphingomyelin.
• Types C: Mutations in NPC1 or NPC2 cause Niemann–Pick disease, type C (NPC), which affects a protein used to transport lipids. It is the most common form of the disease including types C1 (95% of type C) and C2.
• Treatment: No specific treatment is known for type A and B, but symptoms are treated.

Q1) What is genetic disorder?

A genetic disorder is a medical condition caused by abnormalities or mutations in an individual's DNA or genes. These mutations can be inherited from one's parents or can occur spontaneously during a person's lifetime. Genetic disorders can affect various aspects of a person's health, including physical and mental development, organ function, and overall well-being.

Source: List Niemann-Pick as rare disease, parents of young patients urge govt