Inheritance of Muscular Dystrophy Muscular Dystrophy is a condition that affects the growth of muscles in the body. MD effects for the most part manly males (1 in every 7,250 males) (CDC.gov). There are two main forms of MD, one is call Duchenne MD and the other Becker MD with a lifespan average of 30 years old. Duchenne MD is the more severe form because no dystrophin is formed, when this happens the symptoms are shown in early childhood usually by age 5. Becker MD is not as severe it is caused by misshapen dystrophin, when this happens symptoms are shown later in life usually at age 10-20. Researchers identified that a gene in the X chromosome that when flawed it is the cause of MD. Dystrophin is the gene that is needed in the X chromosome to have fully functioning muscle development. MD is inherited in only the X chromosome so males have a 50% chance of inheriting the condition if the mother is a carrier, but females have a very low risk because they get an X chromosome from both mother and father. This condition is an X-linked recessive pattern. If a female inherits a mutated dystrophin gene from one of her parents, she will usually get a healthy dystrophin gene from her other parent because the father can pass the recessive gene in the X chromosomes. The female becomes a carrier just like her mother because the mutation is still in her genes . A male who mother who’s is a carrier has a 50% chance of inheriting the mutation and if they do inherit the gene they will develop the disease because they can not rely on …show more content…
It is a X-linked recessive gene that is pass down from the mother and affects the development growth of males offspring, and also can be passed down to the female offspring but very really.. MD has a high inheritance rate of 50% in males. Males can not pass MD to the offsprings. MD is a really interesting but sad diseases because of the inheritance and
Boys begin to have difficulty sitting up and standing, weakness that progresses to muscles in the trunk and shoulder, and later affecting the heart muscle. By the age of twenty years individuals affected with Duchenne dystrophy die.
Duchenne muscular dystrophy was first discovered by Guillaume Benjamin Amand Duchenne in the 1860’s, but due to lack of medical knowledge little was known until the 1980’s. It was in 1986 that researchers that were supported by the MDA, muscular dystrophy association, identified the particular X-chromosome that leads to DMD, Duchenne muscular dystrophy. Dystrophin is the protein that is associated with the gene and was named in 1987.The DMD gene is the second largest gene to date, and it produces dystrophin.(Genome, 2013) Lack of the protein Dystrophin in the muscle cells causes them to weaken and become fragile. (MDA, 2015). DMD is an inherited disorder, but there are rare cases where it can spontaneously appear in a child with no previous family history due to a random mutation in moms X-chromosome. DMD is a gender specific disease that only appears in males.
According to the " Muscle Diseases" by Patrick F.Chinnery in the Goldman's Cecil Medicine, 24th Ed 2012, "Duchenne Muscular Dystrophy affects about 1 in 3500 males. About one third of the cases arises from a de novo mutation without a family history."
Individuals who inherit this disease will have a rapid progression of symptoms. Walking becomes difficult and skeletal contractures and muscle atrophy follows. They also usually need wheelchairs by adolescence. Half of the receivers of the disease unfortunately develop some form of mental retardation and most never make it past their teenage years. Currently, options for a treatment of muscular dystrophy are limited. Physical therapy may slow down the progression of deformities. Such devices as wheel chairs, crutches, or secondary orthopedic limbs may permit mobility. There are also a few medications that can help relieve pain and stiffness in the muscles. The Muscular Dystrophy Association, the Parent Project Muscular Dystrophy Research and the Children's Hospital of Pittsburgh helped fund a research project for the disease. The research, carried out by Johnny Huard, Ph.D., is looking fairly successful. Scientists are isolating special
Duchenne muscular Dystrophy (DMD) is the most common out of nine types of muscular dystrophy. This genetic disorder causes progressive muscular weakness, and deterioration due to the lack of a protein called Dystrophin. This protein keeps the muscles in tack, so when it's missing, the muscles slowly break down. (MDA, 2015)
Duchenne Muscular Dystrophy (DMD) is a fatal genetic disorder that is caused by mutations in the gene DMD, which encodes the muscle protein, dystrophin. Dystrophin protein is crucial to preserve the strength, stability, and flexibility of muscle fibers, which protects them from injury as they contract and relax. The DMD gene is primarily located in skeletal and cardiac muscle. Duchenne Muscular Dystrophy is caused by mutations in the gene that produce premature stop codons. The premature stop codons work to bring protein synthesis to a halt, resulting in a greatly shortened and nonfunctional form of dystrophin (Pierce, 2013, pg. 286). According to the Muscular Dystrophy Association (2016), “Individuals with DMD experience rapid progressive
The cause of Duchenne Muscular Dystrophy is the occurrence of mutations in the Dystrophin (DMD) gene. The cytogenetic location off the DMD gene is Xp21.2; meaning at location 21.2 on the short arm of the X chromosome from base pair 31,119,219 to base pair 33,339,609. DMD is the biggest human gene currently known and instructs for the production of a 427 kDa protein by the same name. The dystrophin protein is part of the dystrophin associated protein complex which is expressed at the sarcolema and anchors muscle cellcytoskeletons to the extracellular matrix in skeletal and cardiac muscle,
Duchenne’s muscular dystrophy (DMD) is a progressive genetic disorder that leads to muscle atrophy and eventually death. Diagnosing DMD consists of blood tests, genetic testing, and muscle biopsies. Signs and symptoms begin presenting in toddlers with DMD and progressively worsen throughout life. There is no cure for DMD, and will cause terminal cardiopulmonary complications. Medical interventions consist of corticosteroid treatment, respiratory management, cardiac management, psychological management, and physical therapy interventions.
Duchenne muscular dystrophy (DMD) is caused by a mutated gene in the X chromosome. This flawed genes is passed on by the mother. However, most carrier of the gene do not show signs or symptoms of the disease. The The flawed gene causes the improper production of the protein dystrophin which is accompanied by “defective dystrophin-glycoprotein complex (DGC) in the sarcolemma and leads to progressive muscle degeneration” (Nakamura & Takeda, 2011). The Dystrophin protein is vital in providing a muscle integrity. Therefore, the absence of dystrophin production can lead to muscled atrophy.
Duchenne Muscular Dystrophy is one of the most severe yet common cases of Muscular Dystrophy that occurs mainly in boys of younger age. Guillaume Benjamin Amand Duchenne, who was a French neurologist, was the first to discover this disorder in the 1860s (Emery, 2008, pp. 25). This disease is an X-linked disorder which affects the skeletal system, and causes rapid muscular weakness and heart muscle problems. It’s stated that 1 out of every 3,600 males will be diagnosed with Duchenne Muscular Dystrophy (Bushby, 2009, pp.1). According to the Muscular Dystrophy Association, symptoms usually begin to show between the ages of 3 to 5 years old. (pp. 1) Some of the symptoms may include delayed in walking, regularly falling, learning difficulties,
Genetic disorder has many diagnostic and common names for example, DMD is also known as Duchenne muscular dystrophy or Becker and pseudohypertrophic muscular dystrophy. DMD is a genetic disease that occurs mostly in boys. According to the “Muscular Dystrophy Association DMD is inherited in an X-linked pattern, because the gene that can carry a DMD-causing mutation is on the X chromosome. The male host inherits an X chromosome from his mother and a Y chromosome from his father, which is what makes him male. The female host inherits two X chromosomes, one from each parent.” (MDM). “The human X chromosome carries regions prone to genomic instability: deletions in the Xp22.31 region, involving the steroid sulfatase gene cause X-linked ichthyosis; rearrangements in the Xp21.2 region are associated with Duchenne or Becker muscular dystrophies (DMD or BMD); and the Xq27.3 unstable region, containing the (CGG) in repeat expansion in the FMR1 gene is associated with fragile X syndrome stated in the article, “A Family with Fragile X Syndrome, Duchenne Muscular Dystrophy and Ichthyosis Transmitted By An Asymptomatic Carrier”(Todorova, A)
Muscular dystrophy (MD) is a group of genetically transmitted diseases characterized by progressive symmetric wasting of skeletal muscles without evidence of neurologic involvement (Lewis, 2011). There are four different types of muscular dystrophy. The four types are Duchenne, Becker, Landouzy-Dejerine, and Erb. Duchenne muscular dystrophy is the most common type among children. It only affects boys; it’s passed down from the mother. Duchenne muscular dystrophy is created from X-linked recessive gene from the mother. About one in thirty-five hundred boys are born with Duchenne muscular dystrophy. The boys will experience weakening of the muscles, wasting and contractures and inability to walk by themselves by the time they even reach
Duchenne Muscular Dystrophy is the most common form of MD that usually affects children. It has accounted for over 50% of all muscular dystrophy cases, occurring at a frequency of 1 in 3,500 new born males (NCBI 2016). Boys are the main victim of this disease, however symptoms can be shown and experienced by girls and women who carry the defective DMD gene (NIH 2016). It is a terrible disease that is progressive and has a rapid onset. The DMD gene is big in size which makes it an easy
Muscular dystrophy is a genetic disorder that causes progressive deterioration of muscles. This essay is going to focus on Duchenne Muscular Dystrophy (DMD) as it is the most common type of muscular dystrophy in Australia and throughout the world. It is also one of the most severe forms, with many patients in wheelchairs by their mid-teens (Muscular Dystrophy Foundation, 2014). It is estimated that DMD affects 1 in 5000 boys and patients will present with symptoms around the age of 4. Patients may have a range of symptoms including; motor delays, abnormal walking, difficulty getting off the ground, frequent falls and learning difficulties. Eventually DMD can manifest into cardiac and respiratory problems (Yiu and Kornberg, 2015).
A wider base of support along with ITB contractures is commonly associated with the disease. Functional activities may still be conserve until the age of 6 or 7, by the age of 9-10 a rapidly decline of functional activities is observable. On the other hand Becker muscular dystrophy is the mildest version of the muscular conditions, individuals can maintain independent ambulation until the age of 16. Etiology for BMD its very similar to DDM, however dystrophin production its sufficient with good quantity and quality which will allow the breakdown to occur at slower rate than DDM. Symptoms for BMD its usually present between the age of 5 and 15, however the onset is variable, patients usually live until their fourth decade (Tecklin, 2015). Other clinical presentation associated with both conditions are Cardiac, Gastrointestinal, Cognitive, and Respiratory involvement.