Muscular Dystrophy

At least 1 in 3000 people is affected by a serious inherited neuromuscular disorder; muscular dystrophy makes up an appreciable amount of these. (Azofeifa,1995)

Muscular Dystrophy is a heterogeneous group of inherited disorders characterized by progressive muscle wasting and weakness. There are six types of muscular dystrophy: Duchenne muscular dystrophy (DMD), Becker muscular dystrophy, Limb girdle, fasioscapulohumeral, distal, and oculopharyneal.

Duchenne type muscular dystrophy (also known a Meryon’s disease) is the most common form of dystrophy. It mainly only effects boys because it is inherited as an X linked recessive trait. It is probably the most serious form of dystrophy there is because it causes most boys to start using a wheel chair by the age of 12 and causing them to die by there 20’s. This disease causes some of the boys to have some degree of intellectual impairment. ( Kunkle, 1985) (Murray,1982)

Becker type muscular dystrophy is a lot alike with Duchenne but milder. The onset of this does not occur until they’re teenage years and early 20’s. Later in life they may lose the ability to walk, but they live until their middle ages and beyond (Murray,1982)

Over the past couple of years clinical features of weakness of the facial, scapulohumeral, anterior tibial, and pelvic girdle muscle have been extended to include retinal vascular disease, sensory hearing loss and, in severe cases, even abnormalities of the central nervous system. Most people are only mildly affected by this but many become dependent on wheelchairs later on in life. This is condition is inherited as an autosomal dominant trait. In 1990 the gene that is responsible was located on chromosome 4.14 restriction enzyme DNA fragments associated with the gene have been found to be greater than 35 kilobases in length in people who do not have muscular dystrophy. Then the people who are affected are always less than this (measured on an electrophoretic gel). We can then use the difference for suspected presymptomatic cases and in prenatal testing. (Murray,1982)

Limb girdle is a clinically and genetically heterogeneous group of conditions. Limb girdle is caused by a muscle specific protease deficiency. Less then 10 % of cases are inherited through autosomal dominant trait and are mostly mild. One sub type may be allelic to autosomal Emery- Dreifuss dystrophy. All other cases are inherited as autosomal recessive traits affecting both male and female. ( Azofeifa, 1995), (Matthews, 1996), (Perloff, 1967)

Distal myopathies are associated with wasting and weakness of the distal muscle, usually without the noticeable involvement of other muscle groups. Most people with this are only mildly affected although some may ultimately develop serious problem with walking and everyday life. (Padberg, 1997)

Oculopharyngeal (Bareau’s disease) is an autosomal dominant disorder that has been largely described as occurring in French Canadians descending from a couple who immigrated in 1634. The onset of this disease is late in adulthood of progressive ptosis and dysphagia, which is followed by involvement of other cranial and limb muscle. This gene is located on the 14th chromosome. This disease is likely to be genetically homogeneous but with different ancestral mutations in different populations. ( Bakker, 1997), ( Essen, 1997)

Molecular biological techniques have made the prevention of most forms of dystrophy possible through genetic counseling and prenatal testing. There also have been some major advances in the management of the disease. No matter what type of disease or what stage the disease is in certain things you should consider. Eat a well-balanced diet with plenty of fiber to help with constipation, especially when a person becomes immobile. You need to be on the lookout for excessive weight gain. Never let a person stay in bed for a long period of time because it can accelerate weakening of the muscles. You should have everyday activity that is within the person’s own limits. One sport that would be great would be swimming as long as it is supervised. You need to take good care of the respiratory system. Any time there is an infection it must be treated quickly and thoroughly. Surgical correction of scoliosis can make sitting easier and help preserve the lung functions. As the disease becomes older assisted ventilation may be something they might have to do. The quality of life of people with this disease can be much improved by a positive attitude to management, which includes respiratory care, physiotherapy, and surgical correction of contractures. (Bakker, 1997), ( Emery, 1969),

(Holding, 1993), (Kunkle, 1985), ( Reddy, 1984)

The research on this treatment has been mainly concentrated on Duchenne-type muscular dystrophy because of its frequency and severity. They have found that steroids help but they only slow the progression of the diseases for a time. They have not found a drug with any appreciably effects of the long-term course of the disease. Once they begin to understand the pathogenic pathways of the disease they may be able to come up with a drug that can interrupt those pathways. One prospect that looks great would be to upregulate a protein that would compensate for the deficiency of dystrophin. They can’t find a compound that will work in humans. ( Codd, 1989), ( Emery, 1993)

There are some things that a teacher may need to do if he or she has a child in their classroom that has muscular dystrophy. One thing is that most of the time the child will be a boy because the gene that has this defect is in the X chromosome and it that is a boy gene. This disease effects the muscles and causes them to become very weak. Which results in most boys being in a wheel chair by the time they are 12. You can prepare your other children in the classroom by explaining the disease to them and teaching them about wheel chairs and how they help the child to move freely and also teach them not to be afraid of them. Also with this disease some boys will have some intellectual impairment and in some cases special schooling may be needed. You may also want to teach the children about being overweight because some of these children may be overweight because excessive weight gain can sometimes be a problem because the child may be immobile. Another thing you may want to teach the children in your classroom is that they should help encourage the disabled student to engage in everyday activities that are within the children’s limits. For example if everyone is outside playing basketball you could encourage them all to play and then the child in the wheelchair can be included by being able to pass the ball and even shoot the ball. Another example is you could have the children have a race and get a chair on wheel that the other children could sit on and race the child in the wheel chair with. One last thing you could do is teaching all the children to encourage each other to eat a well-balanced diet because children with MS need to have a well-balanced diet to stay healthy.

Bibliography:

Azofeifa J, Voit T, Hubner C, Cremer M. X chromosome methylation in manifesting and healthy carriers of MS. Hum Genet 1995;96: 209-220.

Bakker E, Boten EJ, de Lange LF, et al. DNA probe analysis for carrier detection and prenatal diagnosis MS. JMed Genet 1997; 34: 805-812.

Bakker E, van Broeckhoven C, Boten EJ, van de Vooren MJ, Veenema H, van

Hul W, et al. Germline mosaicism MS mutations. Nature 1987; 329: 554-558

Codd MB, Sugrue DD, Gersh BJ, Melton IIILS. Epidemiology of idiopathic dilated and hypertropic cardiomyopathy. Circulation 1989; 80: 564-572.

Emery AEH. Abnormalities of the electrocardiogram in female carriers of MS. Br Med J 1969; 2: 418-420.

Emery AEH. MS. 2nd ed. Oxford: Oxford University Press, 1993.

Essen van AJ, Kneppers ALJ, Hout van de AH, et al. The clinical and molecular genetic approach to MS: an updated protocol. Jmed Genet 1997; 34: 805-812.

Holding C, Bently D, Roberts R, Bobrow M, Matthew C. Development and validation of laboratory procedures for preimplantation diagnosis of MS Jmed Genet 1993; 30: 903-909.

Kunkle LM, Monaco AP, Middlesworth W, Ochs HD, Latt SA. Specific cloning of DNA fragments absent from DNA of a male patient with an X chromosome deletion. Proc Natl Acad Sci USA 1985; 82: 4778-4782.

Matthews PM, Benjamin D, van Bakel I, et al Muscular inactivation patterns and dystrophin expression in MS carriers. Neuromuscul Disord 1996; 96: 167-176.

Murray JM, Davies KE, Harper PS, Meridith L, Mueller CR, Wiliamson R.Linkage relationship of a cloned DNA sequence on the short arm of the X chromosome to MS. Nature 1982; 300: 69-71

Padberg GW, Lunt PW, Koch M, Fardeau M, Royal Society of Medicine, 1997:

9-15.

Perloff JK, Roberts WC, de Leon AC, O’ Doherty D. The distinctive electrocardiogram of MS. Am Jmed 1967; 42: 179-188.

Reddy BK, Anandavalli TE, Reddi OS. X linke MS in an unusual family with manifesting carriers. Hum Genet 1984; 67: 460-462.

World Book Ency. 1994. Vol 13. Pg.936-937.

Http://lef.org/protocols/prtcl-079.shtml.