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Myotonic dystrophyPy : Jehad abdullah aliTo find out what is the Muscular DystrophyTo find out what is the Myotonic dystrophyTo learn symptoms of Myotonic dystrophyTo be know how to manage the Myotonic dystrophy Muscular Dystrophya group of hereditary progressive diseases. Muscular Dystrophy affects muscular strength and action
Muscle FibersMuscles are made of bundles of fiber (cells). A group of independent proteins along the membrane surrounding each fiber helps to keep muscle cells working properly.When one of these proteins, dystrophin, is absent the result is MD
introductionMyotonic dystrophy is part of a group of inherited disorders called muscular dystrophies. It is the most common form of muscular dystrophy that begins in adulthood.Myotonic dystrophy is an inherited disorder of muscle function.There are two major types of myotonic dystrophy: type 1 and type 2 How common is myotonic dystrophy?affects at least 1 in 8,000 people worldwide.The prevalence of the two types of myotonic dystrophy varies among different geographic and ethnic populations.In most populations, type 1 appears to be more common than type 2. However, recent studies suggest that type 2 may be as common as type 1 among people in Germany and Finland.SYMPTOMS OF MYOTONIC DYSTROPHYThe symptoms of myotonic dystrophy vary greatly from person to person1-MyotoniaDelayed relaxation of a muscle after an initial contraction.Myotonia is most evident in the hands, and results in difficulty releasing grip and a feeling of muscle stiffnessMyotonia can be diagnosed by an electromyogram (EMG)
2- Muscle weaknessThe muscles of the face are often the first to show weakness, resulting in a lack of facial expression or mask-like appearance of the face (myotonic facies)slurred speech (dysarthria)droopy eyelids
mask-like appearance of the face (myotonic facies) with droopy eyelidsMuscle weakness contThe muscles of the lower leg, ankle, foot, forearm and hand are usually the next group of muscles to show weakness.This lead to difficulty with walking, and with finger and hand movements.The muscles involved with breathing and swallowing may become weak over time3- cloudiness of the lens of the eyeThe majority of persons with myotonic dystrophy will eventually develop cataracts (cloudiness of the lens of the eye) that cause vision to become blurry. Cataracts are often the first recognized sign of DM. They can occur in persons without DM, especially in the elderly. In DM however, cataracts develop at a younger age, usually in the forties or fifties. Cataracts are treatable through surgery
cataracts4- Abnormalities of heart rhythm (arrhythmia)
*Other symptoms seen in some but not all persons with DM
DM describedDM is described as being mild, classical or congenital based on the severity and age of onset of symptoms-At this time, there is no treatment or cure that can prevent the symptoms of myotonic dystrophy-
SYMPTOMS OF MAYOTONIC Dystrophy Type 2The symptoms of DM2 are very similar to those of DM, and both conditions are inherited in the same way. The main difference between them is at the genetic level. The genetic change that causes DM2 is different from DM INHERITANCE OF DM
DM is inherited in an autosomal dominant patternDM is caused by a change or mutation in a specific gene, called the myotonic dystrophy protein kinase (DMPK) gene, which is essential for normal muscle and body function.
Every person has 23 pairs of chromosomes, which contain two copies of each gene. The DMPK gene is gif myotonic dystrophy protein kinase and located on chromosome number 19.
The DMPK gene is located on the long (q) arm of chromosome 19 at position 13.3.More precisely, the DMPK gene is located from base pair 45,769,708 to base pair 45,782,556 on chromosome 19.The genetic change that causes DM is called a CTG repeat expansionCTG represents a specific pattern of DNA. It is normal to have between 5 to 37 CTG repeats in both copies of the DMPK gene.
DM2 is also inherited in an autosomal dominant pattern. The gene for DM2 is CNBP (also known as ZNF9) gif nucleic acid binding protein , localized to chromosome number 3.
The CNBP gene is located on the long (q) arm of chromosome 3 at position 21.More precisely, the CNBP gene is located from base pair 129,167,814 to base pair 129,183,966 on chromosome 3Non-molecular testingElectromyography (EMG). A needle electrode placed in the muscle of an affected adult records myotonic discharges
Serum CK concentration. Serum CK concentration may be mildly elevated in individuals with DM1 with weakness, but is normal in asymptomatic individuals.Molecular Genetic TestingMolecular genetic testing detects mutations in nearly 100% of affected individuals.ManagementTreatment of manifestationsmanagement of painconsultation with a cardiologist for symptoms or ECG evidence of arrhythmiaSurveillance eye examination every two yearsattention to nutritional status