What is "distal muscular dystrophy"

n. a form of muscular dystrophy that sets in between 40 and 60 years of age and is characterized by weakness and wasting of the muscles of the hands and forearms and lower legs; inheritance is autosomal dominant

Distal muscular dystrophy (or distal myopathy) is a group of disorders characterized by onset in the hands or feet. Many types involve dysferlin, but it has been suggested that not all cases do.

Types include:

Name

OMIM

Locus

Miyoshi myopathy (in Japan)

DYSF at 2p13.3-p13.1

Distal myopathy with anterior tibial onset

DYSF at 2p13.3-p13.1

Welander distal myopathy

TIA1 at 2p13

DYSF is also associated with Limb-Girdle muscular dystrophy type 2B.

Distal muscular dystrophy is a type of muscular dystrophy that affects the muscles of the extremities, the hands, feet, lower arms, or lower legs. The cause of this dystrophy is very hard to determine because it can be a mutation in any of at least eight genes and not all are known yet. These mutations can be inherited from one parent, autosomal dominant, or from both parents, autosomal recessive. Along with being able to inherit the mutated gene, distal muscular dystrophy has slow progress therefore the patient may not know that they have it until they are in their late 40’s or 50’s. There are eight known types of distal muscular dystrophy. They are Welander’s distal myopathy, Finnish (tibial) distal myopathy, Miyoshi distal myopathy, Nonaka distal myopathy, Gowers-Laing distal myopathy, Hereditary inclusion-body myositis type 1, Distal myopathy with vocal cord and pharyngeal weakness, and ZASP-related myopathy. All of these affect different regions of the extremities and can show up as early as 5 years of age to as late as 50 years old. Doctors are still trying to determine what causes these mutations along with effective treatments.