Congenital muscular dystrophy (CMD) describes a number of different inherited neuromuscular conditions that usually show symptoms at birth or from a very early age. It is estimated that 1 baby in every 20,000-50,000 is born with congenital muscular dystrophy. The different types of CMD are caused by mutations in different genes and can have different symptoms.
All congenital muscular dystrophies affect the muscles. Some also affect the brain. This means some children have muscle weakness involving all or some muscle groups but have normal intelligence, while others may have muscle weakness and learning difficulties.
Babies with congenital muscular dystrophy often appear “floppy” (this may also be described by doctors as low muscle tone or hypotonia). Contractures (tightness) in the joints – ankles, hips, knees and elbows – are also common. Some babies may also have respiratory problems because their breathing muscles are weak.
Most forms of CMD are inherited in an autosomal recessive pattern, which means that in order for a child to be affected, both parents must be carriers of the abnormal (mutated) gene and both must pass this gene on to their child. The parents will normally be unaffected carriers if they only have one copy of the mutated gene. In a few forms however, the condition is due to autosomal dominant mutations. These typically occur de-novo in the affected child, i.e. they are a ‘mis-spelling’ in the genetic code of just that child and not in the parents.
More information can be found at: