A Registered Observational Cohort Study of Myotonic Dystrophy Type 1

Condition(s) studied

Investigational drug(s) / intervention(s)

Triplet-primed PCR or Long-read sequencing: This study involves long-read sequencing in patients with Myotonic Dystrophy Type 1 (DM1) to identify specific motifs, determine the range of repeat numbers, and assess the presence of interruptions in the CTG repeat sequence. The aim is to gain insights into the genetic variability and its clinical implications in DM1.

Study summary

Myotonic dystrophy type 1 (DM1) is the most common form of muscular dystrophy.There is little phenotype and genetic data for Chinese DM1 patients. The data to be collected is intended to fill this gap and provide complementary data

Eligibility

Primary outcome measure(s)

• Triplet-primed PCR or Long-read sequencing — Baseline
  Genetic test of triplet-primed PCR or long-read sequencing is performed for these clinical suspected DM1 patients on the basis of the family as a whole. Eligible participants are genetically confirmed patients With CTG repeats \>50 in DMPK gene.
• Muscle Impairment Rating Scale (MIRS) — Baseline through study completion (an average of 1 year)
  This scale evaluates muscular impairment severity according to an ordinal 5-point scale as follows: (1) no muscular impairment, (2) minimal signs, (3) distal weakness, (4) mild to moderate proximal weakness, and (5) severe proximal weakness.
• The modified Medical Research Council (MRC) scale — Baseline through study completion (an average of 1 year)
  The modified Medical Research Council (MRC) scale is used to assess numerically the muscle strength of DM1 participants. Firstly, muscles are tested bilaterally (when applicable) in standardized positions with manual muscle testing (MMT) scores. Then, MMT scores are converted to calculable data of the modified MRC scale.

Trial sites (1)

More First Affiliated Hospital of Fujian Medical University trials in China