Inclusion Cell Disease, also known as I-cell disease or Mucolipidosis II, is a rare genetic disorder characterized by the dysfunctional transport and processing of proteins in the cells. It is classified as a lysosomal storage disorder, as it affects the lysosome, an organelle responsible for the breakdown of waste materials.
In individuals with Inclusion Cell Disease, a genetic mutation causes a deficiency or absence of the enzyme responsible for tagging proteins with a specific marker known as a mannose-6-phosphate (M6P) group. Without this marker, the proteins cannot be properly transported to the lysosome for processing and degradation. Consequently, these proteins instead accumulate in the cell, forming inclusion bodies or storage bodies.
This disorder affects various bodily systems, leading to a range of symptoms including skeletal abnormalities, developmental delays, intellectual disabilities, impaired growth, coarse facial features, and organ dysfunction. Additional signs may include joint stiffness, hernias, heart valve abnormalities, and respiratory difficulties.
Inclusion Cell Disease is inherited in an autosomal recessive manner, meaning that an individual must inherit two copies of the mutated gene (one from each parent) to develop the disorder. As a rare disease, its occurrence is estimated to be less than one in every 1 million births.
There is currently no cure for Inclusion Cell Disease. Treatment primarily focuses on managing individual symptoms and providing supportive care. Early intervention, including physical and occupational therapy, can help improve motor skills and enhance quality of life for affected individuals.
