Belt dystrophy 2G
Classification according to ICD-10 | |
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G71.0 | Muscular dystrophy - pelvic or shoulder girdle shape |
ICD-10 online (WHO version 2019) |
The limb-2G (LGMD2G) is a very rare disease from the group of limb-girdle muscular dystrophy .
Cause and development of the disease
The LGMD2G is caused by mutations in the TCAP gene (the human chromosome 17, 17q12) gives and autosomal - recessive inherited. TCAP codes for the protein telethonin (titin cap protein). The disease is therefore also known as telethoninopathy . The protein telethonin is produced in the skeletal and heart muscles. It is a sarcomere protein associated with titin and the Z-slices of muscle fibers . So far, homozygous as well as compound heterozygous mutations in the TCAP gene have been described as the cause.
Clinical manifestations
Clinically, the disease is characterized by proximal muscle weakness and the involvement of distal muscle groups and often the heart muscles. The disease usually manifests itself within the second decade of life. Due to the involvement of the distal muscles, the LGMD2G shows similarities with the Miyoshi myopathy .
Investigation methods
The creatine kinase in the serum can be slightly to significantly increased. Typical but unspecific dystrophic changes can be found histologically. Occasionally, "rimmed" vacuoles can be detected, which can lead to confusion with other muscle diseases such as inclusion body myositis and myofibrillary myopathy . A deficiency in telethonin is possible with Western blot analysis or immunohistochemistry . The diagnosis is confirmed by molecular genetics .
treatment
A causal therapy is not known, so symptomatic measures such as physiotherapy are in the foreground.
literature
- AA Amato: Other limb-girdle muscular dystrophies. In: Robert Griggs: Muscular Dystrophies. (= Handbook of Clinical Neurology. Volume 101) 3rd edition. Elsevier, 2011, ISBN 978-0-08-045031-5 , p. 122.
- E. Gordon, E. Pegoraro, EP Hoffman: Limb-Girdle Muscular Dystrophy Overview . Gene Reviews, June 8, 2000, last revision July 23, 2009, freely available as a full text version .
- S. Rauch-Shorny: Genetics of Neuromuscular Diseases: A Selection. In: Journal of Neurology, Neurosurgery and Psychiatry. 2006; 7 (4), pp. 43–56, freely available as a PDF version .
- ES Moreira, TJ Wiltshire et al .: Limb-girdle muscular dystrophy type 2G is caused by mutations in the gene encoding the sarcomeric protein telethonin. In: Nature genetics . Volume 24, Number 2, February 2000, pp. 163-166, ISSN 1061-4036 . doi: 10.1038 / 72822 . PMID 10655062 .
- ES Moreira, M. Vainzof et al: The seventh form of autosomal recessive limb-girdle muscular dystrophy is mapped to 17q11-12. In: American Journal of Human Genetics . Volume 61, Number 1, July 1997, pp. 151-159, ISSN 0002-9297 . doi: 10.1086 / 513889 . PMID 9245996 . PMC 1715843 (free full text), freely accessible as full text.
Individual evidence
Web links
- LGMD2G. In: Online Mendelian Inheritance in Man . (English)