At which manufacturing steps is the aneuploidy of chromosome 21, 18, or 13 verified in the NIPT reference standards?

Genomic DNA is extracted from proprietary maternal and fetal cell lines and validated for chromosome 21, 18, or 13 trisomy by Droplet Digital PCR (ddPCR). After blending, gDNA is accurately and precisely sheared using a mechanical shearing method (, spiked into synthetic matrix II, and aneuploidies are again validated by ddPCR. The euploid control reference standard (HD860) is subjected to the same quality control process. ​The aneuploidies have also been confirmed via Revvity’s Vanadis® cfDNA NIPT platform.