Becker's muscular dystrophy (also known as Benign pseudohypertrophic muscular dystrophy) is an X-linked recessive inherited disorder characterized by slowly progressive muscle weakness of the legs and pelvis. The muscular dystrophies are a group of genetic and hereditary muscle diseases; characterized by progressive skeletal muscle weakness, defects in muscle proteins, and the death of muscle cells and tissue. ... X-linked recessive is a mode of inheritance in which a mutation in a gene on the X chromosome causes the phenotype to be expressed in males (who are necessarily hemizygous for the gene mutation because they have only one X chromosome) and in females who are homozygous for the... Human male pelvis, viewed from front Human female pelvis, viewed from front The pelvis is the bony structure located at the base of the spine (properly known as the caudal end). ...

It is a type of dystrophinopathy, which includes a spectrum of muscle diseases in which there is insufficient dystrophin produced in the muscle cells, resulting in instability in the structure of muscle cell membrane. This is caused by mutations in the dystrophin gene, which encodes the protein dystrophin. Becker's muscular dystrophy is related to Duchenne muscular dystrophy in that both relate to the production of dystrophin, but in Duchenne muscular dystrophy no dystrophin is produced, or it is so abnormal that it cannot be recognized as such. Both Duchenne and Becker's muscular dystrophy have traditionally been called "X-linked" recessive diseases, but in view of modern molecular biology and identification of the dystrophin gene, it might be more appropriate to say they are X-chromosome recessive diseases. Becker's is named after the German doctor Peter Emil Becker. In biology, mutations are changes to the genetic material (usually DNA or RNA). ... This stylistic schematic diagram shows a gene in relation to the double helix structure of DNA and to a chromosome (right). ... A representation of the 3D structure of myoglobin, showing coloured alpha helices. ... Dystrophin is a protein found in membranes surrounding individual muscle fibers, and its deficiency is one of the root causes of muscular dystrophy. ... Duchenne muscular dystrophy (DMD) (also known as pseudohypertrophic muscular dystrophy or muscular dystrophy - Duchenne type) is an inherited disorder characterized by rapidly progressive muscle weakness which starts in the legs and pelvis and later affects the whole body. ...

Genetics

The disorder is inherited with an X-linked recessive inheritance pattern. The gene is located on the X chromosome. Since women have two X chromosomes, if one X chromosome has the non-working gene, the second X chromosome will have a working copy of the gene to compensate. In these cases, some women have much milder symptoms because of this ability to compensate. For example, carrier females of mutations are at increased risk for dilated cardiomyopathy. Since men have an X and a Y chromosome and because they don't have another X to compensate for the defective gene, they will develop symptoms if they inherit the non-working gene. X-linked Recessive inheritance From http://ghr. ... X-linked recessive is a mode of inheritance in which a mutation in a gene on the X chromosome causes the phenotype to be expressed in males (who are necessarily hemizygous for the gene mutation because they have only one X chromosome) and in females who are homozygous for the... Figure 1: Chromosome. ... Cardiomyopathy is the deterioration of the cardiac muscle of the heart wall. ... The term symptom (from the Greek syn = con/plus and pipto = fall, together meaning co-exist) has two similar meanings in the context of physical and mental health: A symptom may loosely be said to be a physical condition which shows that one has a particular illness or disorder (see...

All dystrophinopathes are inherited in an X-linked recessive manner. The risk to the siblings of an affected individual depends upon the carrier status of the mother. Carrier females have a 50% chance of passing the DMD mutation in each pregnancy. Sons who inherit the mutation will be affected; daughters who inherit the mutation will be carriers. Men who have Becker's musculary dystrophy can have children, and all their daughters are carriers, but none of the sons will inherit their father's mutation. Prenatal testing through amniocentesis or Chorionic villus sampling (CVS) for pregnancies at risk is possible if the DMD mutation is found in a family member or if informative linked markers have been identified. Pregnancy Pregnancy is the carrying of one or more embryos or fetuses by female mammals, including humans, inside their bodies. ... Prenatal diagnosis is the diagnosis of disease or condition in a fetus or embryo before it is born. ... Amniocentesis is a medical procedure used for prenatal diagnosis, in which from the amnion around a developing fetus a small amount of amniotic fluid is extracted. ... Chorionic villus sampling (CVS) is a form of prenatal diagnosis to determine genetic abnormalities in the fetus. ...

Becker's muscular dystrophy occurs in approximately 3 to 6 in 100,000 male births. Symptoms usually appear in men at about age 12, but may sometimes begin later. The average age of becoming unable to walk is 25-30. Women rarely develop symptoms.

Genetic counseling is indicated for individuals or families who may carry this condition. Genetic counseling generally refers to prenatal counseling done when a genetic condition is suspected in a pregnancy. ...

Symptoms

1. Muscle weakness, slowly progressive (Difficulty running, hopping, jumping; Progressive difficulty walking)
2. Ability to walk may continue into adulthood (up to age 40)
3. Frequent falls
4. Difficulty breathing
5. Cognitive dysfunction
6. Skeletal deformities, chest and back (scoliosis)
7. Muscle deformities (contractures of heels, legs; Pseudohypertrophy of calf muscles)
8. Fatigue
9. Heart disease

People with this disorder experience progressive muscle weakness of the legs and pelvis, which is associated with a loss of muscle mass (wasting). Muscle weakness also occurs in the arms, neck, and other areas, but not as severely as in the lower half of the body. See Adult. ... Respiration is the process by which an organism obtains energy by reacting oxygen with glucose to give water, carbon dioxide and ATP (energy). ... In biology, the skeleton or skeletal system is the biological system providing support in living organisms. ... Chest of a human male The chest is a part of the anatomy of humans and various other animals. ... Look up Back in Wiktionary, the free dictionary The human back is the large posterior area of the body rising from the top of the buttocks to the back of the neck. ... The heel is the prominence at the posterior end of the foot. ... For the anatomical feature, see calf muscle. ... Fatigue is a state, following a period of mental or physical activity, characterized by a lessened capacity for work and reduced efficiency of accomplishment, usually accompanied by a feeling of weariness, sleepiness, or irritability. ... There are different forms of heart disease: Coronary heart disease Ischaemic heart disease Cardiovascular disease Pulmonary heart disease The study of the heart (and diseases of the heart) is Cardiology. ... In medical circles, wasting refers to the process by which a debilitating disease causes muscle and fat tissue to waste away. ...

Calf muscles initially enlarge (an attempt by the body to compensate for loss of muscle strength), but the enlarged muscle tissue is eventually replaced by fat and connective tissue (pseudohypertrophy). To meet Wikipedias quality standards, this article or section may require cleanup. ... Connective tissue is any type of biological tissue with an extensive extracellular matrix and often serves to support, bind together, and protect organs. ...

Muscle contractures occur in the legs and heels, causing inability to use the muscles because of shortening of muscle fibers and fibrosis of connective tissue. Bones develop abnormally, causing skeletal deformities of the chest and other areas. Fibrosis is the formation or development of excess fibrous connective tissue in an organ or tissue as a reparative or reactive process, as opposed to formation of fibrous tissue as a normal constituent of an organ or tissue. ... Grays illustration of a human femur, a typically recognized bone. ...

Cardiomyopathy (damage to the heart) does not occur as commonly with this disorder as it does with Duchenne's muscular dystrophy. Cognitive problems may accompany the disorder, but they are not inevitable and do not worsen as the disorder progresses.

Signs and tests

The pattern of symptom development resembles that of Duchenne's muscular dystrophy, but with a much slower rate of progression. Muscle wasting begins in the legs and pelvis, then progresses to the muscles of the shoulders and neck, followed by loss of arm muscles and respiratory muscles. Calf muscle enlargement (pseudohypertrophy) is quite obvious. Cardiomyopathy may occur, but the development of congestive heart failure or arrhythmias (irregular heartbeats) is rare. Congestive heart failure (CHF) (also called congestive cardiac failure and heart failure) is the inability of the heart to pump a sufficient amount of blood throughout the body, or requiring elevated filling pressures in order to pump effectively. ... A cardiac arrhythmia, also called cardiac dysrhythmia, is a disturbance in the regular rhythm of the heartbeat. ...

• The ability to walk may continue to age 40 or older.
• Creatine_kinase (CPK) levels may be elevated.
• An electromyography (EMG) shows that weakness is caused by destruction of muscle tissue rather than by damage to nerves.
• Genetic testing
• A muscle biopsy or genetic test (blood test) confirms the diagnosis.

Creatine Kinase Creatine kinase (CK), also known as phosphocreatine kinase or creatine phosphokinase (CPK) is an enzyme (EC 2. ... Electromyography (EMG) is a medical technique for measuring muscle response to nervous stimulation. ... Nerves (yellow)    Nerves redirects here. ... Genetic testing allows the genetic diagnosis of vulnerabilities to inherited diseases, and can also be used to determine a persons ancestry. ... A biopsy (in Greek: bios = life and opsy = look/appearance) is a medical test involving the removal of cells or tissues for examination. ... Blood tests are laboratory tests done on blood to gain an appreciation of disease states and the function of organs. ... Diagnosis (from the Greek words dia = by and gnosis = knowledge) is the process of identifying a disease by its signs, symptoms and results of various diagnostic procedures. ...

Treatment

There is no known cure for Becker's muscular dystrophy. Treatment is aimed at control of symptoms to maximize the quality of life.

Activity is encouraged. Inactivity (such as bed rest) can worsen the muscle disease. Physical therapy may be helpful to maintain muscle strength. Orthopedic appliances such as braces and wheelchairs may improve mobility and self-care. Physical therapy (also known as physiotherapy) is a health profession concerned with the assessment, diagnosis, and treatment of disease and disability through physical means. ... Orthopedic surgery or orthopedics (BE: orthopaedics) is the branch of surgery concerned with acute, chronic, traumatic and recurrent injuries and other disorders of the locomotor system, its musclular and bone parts. ... Wheelchair seating in a theater A lightweight manual wheelchair A wheelchair is a complex medical device used by people for whom walking is difficult or impossible due to illness or disability and incorporates posturally supportive seating, including pressure cushions in many cases. ...

Genetic counseling may be advisable. Sons of a man with Becker's muscular dystrophy do not develop the disorder, but daughters may be carriers. The daughters' sons may develop the disorder.

Support Groups

The stress of illness can often be helped by joining a support group where members share common experiences and problems. Support groups exist to combat or legitimise conditions or behaviours. ...

Expectations (prognosis)

Becker's muscular dystrophy results in slowly progressive disability. Death usually occurs in the fifth decade but some patients live to an advanced age. Prognosis (older Greek πρόγνωσις, modern Greek πρόγνωση - literally fore-knowing, foreseeing) is a medical term denoting the doctors prediction of how a patients disease will progress, and whether there is chance of recovery. ...

Complications

• Deformities
• Permanent, progressive disability manifested as decreased mobility or decreased ability to care for self
• Mental impairment
• Cardiomyopathy
• Pneumonia or other respiratory infections
• Respiratory failure

This article contains material from the CDC (Center for Disease Control) website which, as a US government publication, is in the public domain.[[[[ Hi A mental illness is defined by the medical profession as a disorder of the brain that results in a disruption in a persons thinking, feeling, moods, and ability to relate to others and to work. ... Pneumonia is an illness of the lungs and respiratory system in which the microscopic, air-filled sacs (alveoli) responsible for absorbing oxygen from the atmosphere become inflamed and flooded with fluid. ... Respiratory failure is a medical term for inadequate gas exchange by the respiratory system. ... The public domain comprises the body of all creative works and other knowledge—writing, artwork, music, science, inventions, and others—in which no person or organization has any proprietary interest. ...