Prenatal Diagnosis of Spinal Muscular Atrophy (SMA)
What is SMA?
SMA (Spinal Muscular Atrophy) is a neurological condition and a type of motor neuron disease which a person cannot control the movement of their muscles due to a loss of nerve cells in the spinal cord and brain stem. A person with SMA is unable to move, walk, eat or breathe without assistance.
What causes SMA?
SMA is caused by a mutation in the survival motor neuron gene 1 (SMN1 gene). Motor neurons are the nerve cells that control movement. Abnormal SMN1 gene leads to missing neuron protein critical for nerve function & muscle control.
Types of SMA
What is SMA Carrier?
SMA carrier is a person that has a mutant gene of SMA disease who usually does not display or show symptoms of the disease.
Although carriers are healthy, however, they are able to pass the genetic condition onto their offspring, who may then express the genetic trait.
If both parents are SMA carrier, there is a 25% risk that the offspring have the recessive trait in phenotype.
This test is recommended for people who:
- Have a family history of SMA disease.
- Both partners are carriers of SMA.
- Are closely related by blood (couples with consanguinity).
Sample Requirement:
- Amniotic fluid 15ml
