Clinical value of chromosomal microarray analysis in prenatally diagnosed dextro-transposition of the great arteries.

Objectives: To evaluate the usefulness of chromosomal microarray analysis (CMA) in fetuses with dextro-transposition of the great arteries (d-TGA). Methods: Thirty-two fetuses with d-TGA were examined for submicroscopic copy number variations (CNVs) using CMA. Results: Among the 32 d-TGA fetuses, 23 had isolated lesions (71.9%) and nine had other cardiac or extracardiac anomalies (28.1%). CNVs were detected in 16/32 (50%) of the fetuses, including benign CNVs detected in nine fetuses (28.1%), pathogenic CNVs detected in three fetuses (9.4%), and variants of unknown significance (VOUS) detected in four fetuses (12.5%). There was no significant difference in the detection rates of pathogenic CNVs between the isolated and nonisolated groups. All four VOUS were found in the nonisolated group. Conclusion: CMA might be an effective tool for identifying submicroscopic chromosomal aberrations in fetuses with d-TGA.