Which factor is commonly associated with reduced fetal fraction leading to a no-call in Panorama?

Which factor is commonly associated with reduced fetal fraction leading to a no-call in Panorama?

• A. Advanced paternal age.
• B. Optimized sample handling.
• C. Maternal blood type O.
• D. Higher maternal BMI.

Answer: (D)

Fetal fraction is the portion of cell-free DNA in maternal blood that comes from the fetus. When this fraction is too low, Panorama cannot confidently distinguish fetal DNA from maternal DNA, leading to a no-call. Higher maternal BMI is commonly linked to a reduced fetal fraction. More maternal cfDNA in circulation dilutes the fetal signal, making it harder for the test to reach the threshold needed for a reliable result. Paternal age doesn’t affect fetal fraction, and maternal blood type doesn’t influence it either. Optimized sample handling helps prevent failures due to technical issues and degradation, but it doesn’t inherently reduce fetal fraction.

Fetal fraction is the portion of cell-free DNA in maternal blood that comes from the fetus. When this fraction is too low, Panorama cannot confidently distinguish fetal DNA from maternal DNA, leading to a no-call.

Higher maternal BMI is commonly linked to a reduced fetal fraction. More maternal cfDNA in circulation dilutes the fetal signal, making it harder for the test to reach the threshold needed for a reliable result.

Paternal age doesn’t affect fetal fraction, and maternal blood type doesn’t influence it either. Optimized sample handling helps prevent failures due to technical issues and degradation, but it doesn’t inherently reduce fetal fraction.