Table 1.

Summary of Molecular Genetic Testing Used in Mucolipidosis III Alpha/Beta

Gene 1Test MethodPathogenic Variants Detected 2Variant Detection Frequency by Test Method 3
GNPTABSequence analysis 4Sequence variants>95% 5
Deletion/duplication analysis 6Partial- or whole-gene deletions or duplicationsUnknown; none reported 7

See Molecular Genetics for information on allelic variants.


The ability of the test method used to detect a variant that is present in the indicated gene


Sequence analysis detects variants that are benign, likely benign, of uncertain significance, likely pathogenic, or pathogenic. Pathogenic variants may include small intragenic deletions/insertions and missense, nonsense, and splice site variants; typically, exon or whole-gene deletions/duplications are not detected. For issues to consider in interpretation of sequence analysis results, click here.


Bidirectional sequencing of the entire GNPTAB coding region detects two pathogenic variants in more than 95% of individuals with ML III alpha/beta.


Testing that identifies deletions/duplications not readily detectable by sequence analysis of the coding and flanking intronic regions of genomic DNA; included in the variety of methods that may be used are: quantitative PCR, long-range PCR, multiplex ligation-dependent probe amplification (MLPA), and chromosomal microarray (CMA) that includes this gene/chromosome segment.


Variant detection rate is unknown and may be very low.

From: Mucolipidosis III Alpha/Beta

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