This document provides information about myotonic dystrophy (DM), a hereditary progressive muscle disease. There are two main types, DM1 and DM2. DM is caused by an expanded CTG repeat in the DMPK gene on chromosome 19, while DM2 is caused by a similar mutation in the CNBP gene on chromosome 3. Symptoms vary but can include myotonia, muscle weakness, cataracts, and arrhythmias. There is no cure, but treatment focuses on managing symptoms and surveillance of complications.

1. Myotonic dystrophy
Py : Jehad abdullah ali

2. To find out what is the Muscular Dystrophy
To find out what is the Myotonic dystrophy
To learn symptoms of Myotonic dystrophy
To be know how to manage the Myotonic
dystrophy

3. Muscular Dystrophy
a group of hereditary progressive diseases.
Muscular Dystrophy affects muscular
strength and action

6. Muscle Fibers
Muscles 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

8. Myotonic dystrophy

9. introduction
Myotonic 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

10. 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.

11. SYMPTOMS OF MYOTONIC
DYSTROPHY
The symptoms of myotonic dystrophy vary
greatly from person to person

12. 1-Myotonia
Delayed 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 stiffness
Myotonia can be diagnosed by an
electromyogram (EMG)

14. 2- Muscle weakness
The 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

15. mask-like appearance of the face
(myotonic facies) with droopy
eyelids

16. Muscle weakness cont’
The 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 time

17. 3- cloudiness of the lens of the eye
The 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

18. cataracts

19. 4- Abnormalities of heart rhythm (arrhythmia)
*Other symptoms seen in some but not all
persons with DM

21. DM described
DM 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-

23. SYMPTOMS OF MAYOTONIC
Dystrophy Type 2
The 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

24. INHERITANCE OF DM

26. DM is inherited in an autosomal dominant
pattern
DM 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.

28. 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.

29. The genetic change that causes DM is
called a CTG repeat expansion
CTG represents a specific pattern of
DNA.
It is normal to have between 5 to 37 CTG
repeats in both copies of the DMPK gene.

31. 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 3

32. Non-molecular testing
Electromyography (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.

33. Molecular Genetic Testing
Molecular genetic testing detects mutations
in nearly 100% of affected individuals.

34. Management
1. Treatment of manifestations
 management of pain
 consultation with a cardiologist for symptoms
or ECG evidence of arrhythmia
2. Surveillance
 eye examination every two years
 attention to nutritional status