Myotonic Dystrophy 1 DNA Diagnostic Test

OHSU Service Code:

102-8851

Lab Section:

Molecular Diagnostic Center

Synonyms:

DM; Dystrophica Myotonica 1; Steinert Disease

Test Schedule:

Weekly. Result turnaround in 2 weeks. STAT turn around is available.

Specimen
Requirements:

6.0 mL whole blood in EDTA vacutainer tube. For pre-natal or neo-natal specimens, please call the lab at 503-494-5400. For requisition slips.

Reference Range:

Phenotype                 #CTG Repeats

Normal                     5-35

Premutation                36-49

Affected (adult onset)     50-1000

Affected (congenital)      1000-2000 (in fetuses)

Interpretation:

5-35 CTG repeats	No clinical pheontype
36-49 CTG repeats	No clinical phenotype, or mild clinical phenotype
50-1000 repeats	Affected (adult onset)
1000-2000 repeats	Affected (congenital) in fetuses

Comments:

Testing is diagnostic for normal/disease states with > 99% accuracy. Myotonic dystrophy 1 is the most common form of inherited adult-onset muscular dystrophy. Affected females are at risk for offspring with congenital myotonic dystrophy, characterized by severe hypotonia at birth and learning disabilities or mental retardation. Genetic counseling is indicated for individuals with a family history of DM. Please call the laboratory at 503-494-5400 for more information.