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Miyoshi muscular dystrophy 1(MMD1)

MedGen UID:
Concept ID:
Disease or Syndrome
Synonym: MMD1
Gene (location): DYSF (2p13.2)
Monarch Initiative: MONDO:0024545
OMIM®: 254130

Disease characteristics

Excerpted from the GeneReview: Dysferlinopathy
Dysferlinopathy includes a spectrum of muscle disease characterized by two major phenotypes: Miyoshi muscular dystrophy (MMD) and limb-girdle muscular dystrophy type 2B (LGMD2B); and two minor phenotypes: asymptomatic hyperCKemia and distal myopathy with anterior tibial onset (DMAT). MMD (median age of onset 19 years) is characterized by muscle weakness and atrophy, most marked in the distal parts of the legs, especially the gastrocnemius and soleus muscles. Over a period of years, the weakness and atrophy spread to the thighs and gluteal muscles. The forearms may become mildly atrophic with decrease in grip strength; the small muscles of the hands are spared. LGMD2B is characterized by early weakness and atrophy of the pelvic and shoulder girdle muscles in adolescence or young adulthood, with slow progression. Other phenotypes in this spectrum are scapuloperoneal syndrome and congenital muscular dystrophy. Asymptomatic hyperCKemia is characterized by marked elevation of serum CK concentration only. DMAT is characterized by early and predominant distal muscle weakness, particularly of the muscles of the anterior compartment of the legs. [from GeneReviews]
Masashi Aoki  |  Toshiaki Takahashi   view full author information

Additional descriptions

Miyoshi muscular dystrophy (MMD) is an autosomal recessive skeletal muscle disorder characterized by onset in young adulthood of distal muscle weakness affecting the upper and lower limbs but sparing the intrinsic hand muscles. Muscle weakness and atrophy particularly affects the gastrocnemius and soleus muscles, and can later spread to involve the thigh and gluteal muscles. Patients showed impaired tiptoe standing, difficulty in climbing stairs, and difficulty walking, but usually remain ambulatory. Serum creatine kinase is increased and muscle biopsies show myopathic and dystrophic changes with necrosis (summary by Miyoshi et al., 1986). Genetic Heterogeneity of Miyoshi Muscular Dystrophy Miyoshi muscular dystrophy is a genetically heterogeneous disorder: MMD2 (613318) has been mapped to chromosome 10p, and MMD3 (613319) is caused by mutation in the ANO5 gene (608662) on chromosome 11p14. See also Welander myopathy (604454), an autosomal dominant form of late-onset distal myopathy.  http://www.omim.org/entry/254130
From MedlinePlus Genetics
As Miyoshi myopathy slowly worsens, the muscle weakness and atrophy spread up the leg to the muscles in the thigh and buttock and can also involve the upper arm and shoulder muscles. Eventually, affected individuals may have difficulty climbing stairs or walking for an extended period of time. Some people with Miyoshi myopathy may eventually need wheelchair assistance.

Rarely, abnormal heart rhythms (arrhythmias) have developed in people with Miyoshi myopathy. Individuals with Miyoshi myopathy have highly elevated levels of an enzyme called creatine kinase (CK) in their blood, which often indicates muscle disease.

Miyoshi myopathy is a muscle disorder that begins with weakness in the muscles that are located away from the center of the body (distal muscles), such as those in the legs. During early to mid-adulthood, affected individuals typically begin to experience muscle weakness and wasting (atrophy) in one or both calves. If only one leg is affected, the calves appear different in size (asymmetrical). Calf weakness can make it difficult to stand on tiptoe.  https://medlineplus.gov/genetics/condition/miyoshi-myopathy

Clinical features

From HPO
Lower limb muscle weakness
MedGen UID:
Concept ID:
Weakness of the muscles of the legs.
Decreased Achilles reflex
MedGen UID:
Concept ID:
Decreased intensity of the Achilles reflex (also known as the ankle jerk reflex), which can be elicited by tapping the tendon is tapped while the foot is dorsiflexed.
Decreased/absent ankle reflexes
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Concept ID:
Muscle fibrillation
MedGen UID:
Concept ID:
Fine, rapid twitching of individual muscle fibers with little or no movement of the muscle as a whole. If a motor neuron or its axon is destroyed, the muscle fibers it innervates undergo denervation atrophy. This leads to hypersensitivity of individual muscle fibers to acetyl choline so that they may contract spontaneously. Isolated activity of individual muscle fibers is generally so fine it cannot be seen through the intact skin, although it can be recorded as a short-duration spike in the EMG.
Tip-toe gait
MedGen UID:
Concept ID:
An abnormal gait pattern characterized by the failure of the heel to contact the floor at the onset of stance during gait.
Muscular dystrophy
MedGen UID:
Concept ID:
Disease or Syndrome
The term dystrophy means abnormal growth. However, muscular dystrophy is used to describe primary myopathies with a genetic basis and a progressive course characterized by progressive skeletal muscle weakness and wasting, defects in muscle proteins, and histological features of muscle fiber degeneration (necrosis) and regeneration. If possible, it is preferred to use other HPO terms to describe the precise phenotypic abnormalities.
Difficulty climbing stairs
MedGen UID:
Concept ID:
Reduced ability to climb stairs.
Distal muscle weakness
MedGen UID:
Concept ID:
Reduced strength of the musculature of the distal extremities.
Distal amyotrophy
MedGen UID:
Concept ID:
Disease or Syndrome
Muscular atrophy affecting muscles in the distal portions of the extremities.
Deposits immunoreactive to beta-amyloid protein
MedGen UID:
Concept ID:
Elevated circulating creatine kinase concentration
MedGen UID:
Concept ID:
An elevation of the level of the enzyme creatine kinase (also known as creatine phosphokinase (CK; EC in the blood. CK levels can be elevated in a number of clinical disorders such as myocardial infarction, rhabdomyolysis, and muscular dystrophy.

Term Hierarchy

CClinical test,  RResearch test,  OOMIM,  GGeneReviews,  VClinVar  

Professional guidelines


Nashi S, Polavarapu K, Bardhan M, Anjanappa RM, Preethish-Kumar V, Vengalil S, Padmanabha H, Geetha TS, Prathyusha PV, Ramprasad V, Joshi A, Chawla T, Unnikrishnan G, Sharma P, Huddar A, Uppilli B, Thomas A, Baskar D, Mathew S, Menon D, Arunachal G, Faruq M, Thangaraj K, Nalini A
Neurogenetics 2023 Jan;24(1):43-53. Epub 2022 Dec 29 doi: 10.1007/s10048-022-00707-3. PMID: 36580222
Martins E, Silva-Cardoso J, Silveira F, Nadais G, Gonçalves FR
Rev Port Cardiol 2005 Jan;24(1):23-35. PMID: 15773664

Recent clinical studies


Croissant C, Carmeille R, Brévart C, Bouter A
Int J Mol Sci 2021 May 17;22(10) doi: 10.3390/ijms22105276. PMID: 34067866Free PMC Article

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