Invitae has added non-invasive prenatal screening (NIPS) to its offerings and integrated it as part of the firm's carrier screening test. The NIPS test analyzes cell-free DNA to assess whether a pregnancy is at heightened risk for three common chromosomal disorders, including trisomy 21 (Down syndrome), trisomy 18 (Edwards syndrome) and trisomy 13 (Patau syndrome). There is no additional charge for adding microdeletion and sex chromosome analysis. The carrier screen sequences 301 genes linked to serious genetic disorders, and now the same specimen collection kit will also enable NIPS. Invitae will begin accepting NIPS test orders next week.