Becker muscular dystrophy

From WikiLectures


Becker Muscular Dystrophy ( BMD ) is a genetic disease of the muscles of the human body. This is an X-linked gonosomal recessive inheritance , which is why they are mainly male (99.9%). Women are often carriers , ie. the mutated gene is contained in their DNA, but its recessiveness causes it not to show. Becker muscular dystrophy is generally a milder form of Duchenne Muscular Dystrophy (DMD). The incidence of BMD in the population is about 1: 18,000  .

Genetics[edit | edit source]

Muscular dystrophy is caused by the deletion of a certain part of a chromosome. The distribution of deletions is typical for the spectral repeat region (up to 46%  ). Becker muscular dystrophy accounts for about 15%  of locus mutations .

The fundamental genetic difference between the allelic phenotypes of DMD and BMD is that DMD is genetically lethal , while in BMD, male reproductive capacity is maintained at a high percentage. Therefore, the frequency of inherited mutations is very high and newly created mutations are minimal. Both forms of dystrophy differ in onset and course, not in severity.

A genetic test to detect this disease is expensive because the mutation occurs on one of the largest human genes.

Causes[edit | edit source]

At the molecular level, the causes are different. One of the most common causes of dystrophy is a low concentration or abnormal form of plectin protein in muscle tissue, which is caused by a mutation in the appropriate X chromosome gene . In the muscles, the desmino-plectin system does not bind properly .

Symptoms[edit | edit source]

Becker muscular dystrophy can be detected at the molecular level as early as the prenatal period.

In childhood or early puberty (around 11 years), symptoms begin to appear:

  • general physical weakness (the disabled person is not physically fit, has below-average results in sports,…),
  • muscle cramps.

During adolescence , the symptoms escalate. Appear:

  • difficulty walking fast , walking up stairs, running,
  • difficulties in lifting heavy loads,
  • .
    loss of muscle mass (shoulder, upper and lower limbs),
  • weakening of mimic and masticatory muscles → problem with food intake,
  • weakening of the sphincters → spontaneous leakage of urine or stool ( incontinence ),
  • inability to walk from 40. – 50. year,
  • respiratory problems, heart problems and other symptoms associated with smooth muscle weakness .

Treatment[edit | edit source]

The treatment of the cause is currently unknown.

The course of the disease can be slowed down in the following ways:

  • regular rehabilitation (impact exercise does not make sense),
  • muscle massages,
  • stretching splints (stretching and exercising a muscle in sleep).

Links[edit | edit source]

https://www.wikiskripta.eu/index.php?curid=69228

Related Articles[edit | edit source]

  • Duchenne muscular dystrophy
  • Daltonism
  • Hemophilia

External links[edit | edit source]

  • KAČÍRKOVÁ, Jitka. Becker Muscular Dystrophy (BMD)  [online]. [feeling. 2016-10-23]. < http://www.amd-mda.cz/nervosvalova-onemocneni/diagnozy-typy-nervosvalovych-onemocneni/beckerova-svalova-dystrofie-bmd >.

References[edit | edit source]

  • NUSSBAUM, Robert L, Roderick R MCINNES and Huntington F WILLARD, et al. Clinical Genetics: Thompson & Thompson. 6th edition. Prague: Triton, 2004. 492 pp.  ISBN 80-7254-475-6 .
  • LÜLLMANN-RAUCH, Renate. Histology. 1st edition. Prague: Grada, 2012. 576 pp.  ISBN 978-80-247-3729-4 .

References[edit | edit source]

  1. ↑ KAČÍRKOVÁ, Jitka. Becker Muscular Dystrophy (BMD)  [online]. Association of Muscular Dystrophics in the Czech Republic, © 2016. [feeling. 2017-01-13]. < http://www.amd-mda.cz/nervosvalova-onemocneni/diagnozy-typy-nervosvalovych-onemocneni/beckerova-svalova-dystrofie-bmd >.
  2. ↑ NUSSBAUM, Robert L, Roderick R MCINNES and Huntington F WILLARD, et al. Clinical Genetics: Thompson & Thompson. 6th edition. Prague: Triton, 2004. 492 pp.  ISBN 80-7254-475-6 .
  3. ↑ NUSSBAUM, Robert L, Roderick R MCINNES and Huntington F WILLARD, et al. Clinical Genetics: Thompson & Thompson. 6th edition. Prague: Triton, 2004. 492 pp.  ISBN 80-7254-475-6 .