Muscular Dystrophy Congenital

Description

Muscular Dystrophy Congenital (MDC) is a rare group of disorders that affect muscle development from birth. These disorders are characterized by progressive muscle weakness and wasting, often leading to significant mobility challenges. While there is no cure for MDC, early diagnosis and management can help individuals and their families thrive.

Genes Involved

The specific genes involved in MDC vary depending on the type of the disorder. Some of the genes associated with MDC include:

LMNA: This gene is involved in the production of lamin A/C, a protein that provides structural support to the cell nucleus. Mutations in LMNA can cause various types of muscular dystrophy, including MDC1A.
FHL1: Mutations in this gene are associated with MDC1B, a type of MDC characterized by weakness in the muscles of the face, shoulders, and hips.
RYR1: This gene codes for a protein involved in calcium release in muscle cells. Mutations in RYR1 can cause MDC1C, a type of MDC with muscle weakness and rigidity.
Other genes: Various other genes have been linked to MDC, including genes involved in muscle protein production, muscle fiber development, and nerve function.

Recognizing the Signs and Symptoms

While the severity of symptoms can vary greatly, common signs and symptoms of MDC include:

Delayed motor milestones: Infants with MDC may be slow to reach developmental milestones like rolling over, sitting, or walking.
Muscle weakness: This weakness may be noticeable in different muscle groups, such as the limbs, trunk, or face.
Muscle wasting (atrophy): Muscles may appear smaller than normal.
Contractures: Joints may become stiff and difficult to move.
Breathing difficulties: In severe cases, muscle weakness can affect the muscles involved in breathing, leading to respiratory problems.
Heart problems: Some types of MDC can affect the heart muscle.

Causes

MDC is caused by genetic mutations that affect the development and function of muscles. These mutations can be inherited from a parent or occur spontaneously during the development of the embryo. The specific cause depends on the type of MDC.

Inheritance/recurrence risk

Inheritance or Recurrence Risk

The inheritance pattern of MDC varies depending on the underlying genetic mutation. Some types of MDC are inherited in an autosomal recessive manner, meaning that both parents must carry a copy of the mutated gene for their child to be affected. Other types of MDC are inherited in an autosomal dominant manner, where only one parent needs to carry the mutated gene for the child to develop the condition.

The risk of recurrence for MDC depends on the type of inheritance and the genetic makeup of the parents. Genetic counseling can provide information about the risk of passing on the gene to future children.

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