Carrier screening or diagnostic testing for mucolipidosis type IV for individuals of Ashkenazi Jewish descent.
Polymerase Chain Reaction/Fluorescence Monitoring
Lavender (EDTA), pink (K2EDTA), or yellow (ACD Solution A or B).
Transport 3 mL whole blood. (Min: 1 mL)
Specimens collected in sodium heparin or lithium heparin tubes.
Ambient: 72 hours; Refrigerated: 2 weeks; Frozen: 1 month
Background information for Mucolipidosis, Type IV (MCOLN1), 2 Variants:
Characteristics: Mucolipidosis type IV is characterized by early onset of severe psychomotor delay and progressive visual impairment due to corneal clouding and retinal degeneration. Affected individuals may occasionally learn to say a few words or walk independently. While most affected individuals remain neurologically static until age 30, about 15 percent will display neurological degeneration.
Incidence: 1 in 63,000 Ashkenazi Jewish individuals.
Inheritance: Autosomal recessive.
Cause: MCOLN1 pathogenic variants.
Variants Tested: g.511_6943del and c.406-2A>G.
Clinical Sensitivity: 95 percent in Ashkenazi Jewish individuals, 6 to 10 percent in other ethnicities.
Methodology: Polymerase chain reaction (PCR) and fluorescence monitoring.
Analytical Sensitivity and Specificity: Greater than 99 percent.
Limitations: Variants other than g.511_6943del and c.406-2A>G will not be detected. Diagnostic errors can occur due to rare sequence variations.
Compliance Statement C: For human genetic inheritable conditions and mutations. This test was developed and its performance characteristics determined by ARUP Laboratories. The U. S. Food and Drug Administration has not approved or cleared this test; however, FDA clearance or approval is not currently required for clinical use. The results are not intended to be used as the sole means for clinical diagnosis or patient management decisions.
Counseling and informed consent are recommended for genetic testing. Consent forms are available online.
|Component Test Code*||Component Chart Name||LOINC|
|0051450||Mucolipidosis IV (MCOLN1), Allele 1||34658-5|
|0051451||Mucolipidosis IV (MCOLN1), Allele 2||34658-5|
|0051452||Mucolipidosis IV (MCOLN1), Interp||46965-0|
|2001329||Mucolipidosis IV (MCOLN1), Specimen||31208-2|