Myasthenia Gravis
Description
Myasthenia Gravis (MG) is a chronic autoimmune disorder that affects the muscles responsible for voluntary movement. In MG, the body‘s immune system mistakenly attacks the neuromuscular junction, the point where nerve signals are transmitted to muscles. This disrupts the communication between nerves and muscles, leading to muscle weakness and fatigue.
Genes Involved
Genes Involved in Myasthenia Gravis:
- AChR (Acetylcholine Receptor): The gene encoding the acetylcholine receptor is the primary target of the autoimmune attack in MG.
- MuSK (Muscle-Specific Kinase): A gene encoding an enzyme crucial for neuromuscular junction development.
- Lrp4 (Low-Density Lipoprotein Receptor-Related Protein 4): A gene involved in regulating the AChR.
Recognizing the Signs and Symptoms
Recognizing the Signs and Symptoms of Myasthenia Gravis:
- Muscle Weakness: The most common symptom is muscle weakness that worsens with activity and improves with rest. It often affects the eye muscles, causing double vision (diplopia) or drooping eyelids (ptosis).
- Fatigue: Feeling tired and exhausted, especially after physical exertion.
- Difficulty Swallowing: Difficulty swallowing (dysphagia) can make eating and drinking challenging.
- Slurred Speech: Weakness in the facial muscles can lead to difficulty speaking clearly.
- Muscle Stiffness: Some individuals may experience muscle stiffness or spasms.
- Breathing Difficulties: In severe cases, weakness in the respiratory muscles can make breathing difficult.
Causes
Causes of Myasthenia Gravis:
- Autoimmune Disorder: The main cause is an autoimmune reaction where the body‘s immune system mistakenly attacks the acetylcholine receptors at the neuromuscular junction.
- Genetic Predisposition: Having a family history of MG increases the risk.
- Environmental Factors: Certain infections, such as viral infections, may trigger the development of MG in genetically predisposed individuals.
Inheritance/recurrence risk
Inheritance or Recurrence Risk:
- Genetic Inheritance: While not directly inherited, MG has a genetic component. Having a close relative with MG increases the risk.
- Recurrence Risk: The risk of developing MG is higher in individuals with a family history. However, the exact recurrence risk can vary depending on factors such as the specific genetic mutation involved and the age of onset.
