What is the incidence of myotonic dystrophy?
Myotonic dystrophy affects at least 1 in 8,000 people worldwide. The prevalence of the two types of myotonic dystrophy varies among different geographic and ethnic populations.
What is myotonic dystrophy type II?
Myotonic dystrophy type 2, one of the two types of myotonic dystrophy, is an inherited muscular dystrophy that affects the muscles and other body systems (e.g., heart, eyes, and pancreas). It is characterized by prolonged muscle tensing (myotonia) as well as muscle weakness, pain, and stiffness.
What is the life expectancy of myotonic dystrophy?
The median survival was 60 years for males and 59 years for females. Survival of the patients was also estimated from the age of 15 years to the ages of 25, 45 and 65 years and compared with the expected survival of age- and sex-matched birth cohorts from the normal Dutch population.
What is the prevalence of myotonic dystrophy?
Myotonic dystrophy (DM) is the most common adult-onset muscular dystrophy with an estimated prevalence of 1/8000. There are two genetically distinct types, DM1 and DM2. DM2 is generally milder with more phenotypic variability than the classic DM1.
What is myotonic dystrophy type 2 (DM2)?
Myotonic dystrophy type 2 (DM2) is characterized by myotonia (90% of affectedindividuals) and muscle dysfunction (weakness, pain, and stiffness) (82%), and less commonly by cardiac conduction defects, iridescent posterior subcapsular cataracts, insulin-insensitive type 2 diabetes mellitus, and testicular failure.
How is myotonic dystrophy (DM) inherited?
Mutation of the DMPK gene causes myotonic dystrophy type 1 (DM1). Mutation of CNBP gene causes type 2 (DM2). DM is typically inherited from a person’s parents, following an autosomal dominant inheritance pattern, and it generally worsens with each generation. A type of DM1 may be apparent at birth. DM2 is generally milder.
What is type 1 myotonic dystrophy (myotonia)?
History. Isolated case reports of myotonia had been published previously, including reports by Frederick Eustace Batten and Hans Curschmann, and Type 1 myotonic dystrophy is therefore sometimes known as Curschmann-Batten-Steinert syndrome. The underlying cause of type 1 Myotonic dystrophy was determined in 1992.