Prenatal Myotonic Dystrophy 1
Use
Prenatal analysis of the DMPK gene for detection of expanded CTG repeats responsible for Myotonic Dystrophy Type 1 (DM1), including the congenital form, which can present prenatally with polyhydramnios and decreased fetal movement and postnatally with severe hypotonia, respiratory insufficiency, feeding difficulties, and early mortality. The test is intended to confirm clinical suspicion in prenatal samples.
Special Instructions
Allele repeat numbers up to 50 are reported with ± accuracy, and 50–200 repeats with ±5 repeats; alleles >200 repeats cannot be quantified precisely using this test and would require Southern blot, which GeneDx does not perform on prenatal samples.
Limitations
For alleles larger than ~200 repeats, the exact number cannot be determined; Southern blot analysis is required for such large expansions, and this method is not available at GeneDx for prenatal samples.
Methodology
PCR-based
Biomarkers
Result Turnaround Time
Not provided.
Related Documents
For more information, please review the documents below
Specimen
Other
Volume
Not provided
Minimum Volume
Not provided
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