Mucolipidosis (ML) is a group of inherited metabolic disorders that affect the body's ability to carry out the normal turnover of various materials within cells resulting in accumulation of abnormal amounts of carbohydrates or fatty materials (lipids) in cells.
Over 90% of the Mucolipidosis type IV disorders occur in Ashkenazi Jewish population where there is a high carrier frequency of 1:90 to 1:100.
This type of mucolipidosis is caused by mutation of a non-selective cation channel, TRPML1, which is localized in endosomes and may function as either a proton leak channel and/or aid in the regulation of calcium levels. There are 10 mutations in TRPML1, located throughout the channel. Three of these mutations (Q79X, R102X and R172X) result in early truncation of the channels and the loss of functional protein. The other seven mutations result in either amino acid substitution or deletion.
Testing criteria and symptoms
Being of Ashkenazi Jewish ancestry
Mild learning disabilities to severe mental retardation and skeletal deformities.
Delayed psychomotor development and various ocular aberrations.