Microarray Reporting: Balancing Laboratory Findings, Clinical Utility and Patient Anxiety

Li E. Cheng, Arun Wiita, Jingwei Yu Yu


Cytogenomic microarray has been increasingly applied in prenatal diagnosis with the advantage of higher resolution and faster turn-around time compared with conventional karyotyping. However, the greater information offered by this technology also leads to special challenges and ethical dilemmas for laboratory cytogeneticists, obstetricians, and patients. These issues are most apparent in reporting results of uncertain clinical significance, which are frequently found by cytogenomic microarray. The reporting of such variants may lead to significant obstetrician unease and patient anxiety, particularly as the results of cytogenomic microarray may often be the primary factor in determining whether to terminate a wanted pregnancy. However, cytogeneticists often feel an obligation to report such variants due to laboratory guidelines or avoidance of future legal liability. Here, we discuss several issues specific to interpreting array results in the prenatal setting, including copy-number-variant size and gene content, penetrance, inheritance, region of homozygosity, mosaicism, maternal cell contamination, and clinical correlation. We propose a practical approach for cytogeneticists to balance complete reporting of laboratory findings with predicted clinical utility and minimization of patient anxiety. Our discussion also highlights the importance of establishing a prenatal array database with longitudinal studies to determine phenotypic outcomes related to variants identified on array, and the central role of genetic counseling in the use of prenatal cytogenomic arrays. Incorporation of these elements and a universal reporting framework will be crucial for more seamlessly integrating cytogenomic array analysis into prenatal care.


prenatal diagnosis, cytogenomic microarray, copy number variant (CNV), variants of uncertain significance (VUS), array reporting

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