Prenatal identification of carrier status for autosomal recessive disorders on chromosomal microarray.

Objective: Chromosomal microarray (CMA) is primarily used for the diagnosis of chromosomal deletions and duplications that have a direct phenotype based solely on that copy number variation (CNV) without other genetic changes. However, CNVs that contain a gene associated with a recessive disorder confer risk for that disorder should a second pathogenic variant be present in the other copy of the gene. The study aimed to propose a protocol to be considered for follow up testing after the detection of CNV containing an autosomal recessive gene on prenatal sample via chromosomal microarray. Methods: We present 5 cases involving prenatal diagnosis where CMA identified changes in an autosomal recessive gene conferring carrier status and discuss management of this finding. Results: Algorithm of selecting different diagnostic genetic testing after the detection of CNV containing an autosomal recessive gene on prenatal sample via chromosomal microarray has been created to help practitioners involved in this process. Conclusion: We recommend that CNV’s involving autosomal recessive genes identified by CMA be treated as any other carrier status. The parents should be encouraged to pursue genetic testing to determine their carrier status of the autosomal recessive conditions and/or additional prenatal diagnostic test on the fetus. [ABSTRACT FROM AUTHOR]