A 32-year-old female presented to OB/GYN at 18 weeks gestation. Mutliple ultrasound anomalies were detected, including postaxial polydactyly, choroid plexus cysts, and omphalocele. Non-invasive prenatal screening (NIPS) via cell-free DNA sequencing was ordered to screen for the presence of common trisomies (13, 18, 21). NIPS revealed a borderline positive result for chromosome 18 (segmentation plot shown below). A prenatal chromosomal microarray was ordered to confirm the screening result, and the results for chromosome 18 are shown:
|Ross Rowsey, Ph.D.
Fellow, Clinical Molecular Genetics
|Hutton Kearney, Ph.D
Consultant, Laboratory Medicine and Pathology
Assistant Professor of Laboratory Medicine and Pathology
Mayo Clinic College of Medicine