Table 1.

Molecular Genetic Testing Used in Myotonic Dystrophy Type 1

Gene 1MethodProportion of Pathogenic Variants 2 Identified by Method
DMPK Targeted analysis for pathogenic variants 3100%
1.
2.

See Molecular Genetics for information on variants detected in this gene.

3.

Testing to quantitate the number of DMPK CTG trinucleotide repeats is performed by PCR analysis, which reliably detects expanded alleles with about 100-150 CTG repeats. Detection of larger CTG expansions requires Southern blot analysis.

From: Myotonic Dystrophy Type 1

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