couple looking at ultrasound photo

Single-gene screening

Dedicated genetic testing
for spinal muscular atrophy

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Screening for Spinal muscular atrophy

In addition to a comprehensive screening for more than 500 genetic disorders (Inheritest), we also offer screening for specific disorders, such as spinal muscular atrophy (SMA).

Why focus on SMA screening?

The purpose of SMA carrier screening is to determine if a couple is at increased risk for having a child with SMA, the leading genetic cause of infant death.1

You could be a carrier of SMA even if no one in your family has SMA and even if you already have children without SMA. Carriers of the abnormal gene have no symptoms of the disorder. As with most inherited disorders, the risk for being an SMA carrier varies by ethnic background2 (see table below).

EthnicitySMA carrier risk in people with no family history of SMA
Caucasian1 in 47
Asian Indian1 in 52
Asian1 in 59
Ashkenazi Jewish1 in 67
Hispanic1 in 68
African American1 in 72

The screening test requires a blood sample or mouthwash and results are typically ready within 5 to 8 days. If a couple has not yet conceived, one partner is usually tested first. If a woman is already pregnant, a couple may opt to be tested at the same time.

If both parents are carriers of an altered SMA gene, there is a chance their child will be affected.

Learn more about how inherited disorders like SMA are passed on.

Additional Resources

References

  1. Carrier Screening for Genetic Conditions. ACOG Committee Opinion No. 691, March, 2017
  2. Sugarman EA, et al. Pan-ethnic carrier screening and prenatal diagnosis for spinal muscular atrophy: clinical laboratory analysis of >72,400 specimens. Eur J Hum Genet 2012; 20:27-32.