Expanded vs. Single-Gene Carrier Screening

Compare expanded carrier screening panels with single-gene tests to choose the right option for your family planning.

Single-gene carrier tests look at one specific gene, such as CFTR for cystic fibrosis or SMN1 for spinal muscular atrophy. They are useful when there is a known family history or when follow-up testing is needed after a positive expanded panel result.

Expanded carrier screening tests many genes at once. Panels can include dozens to hundreds of conditions. The goal is to find carrier status for conditions you might not otherwise think to test for, especially if they are more common in your ethnic background.

Expanded screening is convenient but not exhaustive. It does not test for every possible genetic condition, and the chance of finding an uncertain result increases with the number of genes tested. A genetic counselor can help you decide whether a larger panel is right for you.

Both types of screening use a blood or saliva sample. Turnaround time is usually similar. Cost is often higher for expanded panels, though some labs offer bundled pricing.

ACOG supports offering expanded carrier screening as an option, while emphasizing that patients should understand the benefits and limits of testing.

References

• ACOG Committee Opinion No. 690. Carrier Screening for Genetic Conditions.
• ACMG. Expanded Carrier Screening in Reproductive Medicine.