1. Let the data do the talking: the need to consider mosaicism during embryo selection
- Author
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Mitko Madjunkov, Andrea R. Victor, Svetlana Madjunkova, Francesca Spinella, Rajiv C. McCoy, Clifford Librach, Frank L. Barnes, Manuel Viotti, Christo Zouves, Darren K. Griffin, and Ermanno Greco
- Subjects
Male ,Reproductive Techniques, Assisted ,Aneuploidy ,Genetic Counseling ,Biology ,Bioinformatics ,Article ,Predictive Value of Tests ,Pregnancy ,Prenatal Diagnosis ,medicine ,Humans ,Genetic Testing ,Selection (genetic algorithm) ,Genetic testing ,medicine.diagnostic_test ,Mosaicism ,Reproducibility of Results ,Obstetrics and Gynecology ,Embryo ,Embryo Transfer ,medicine.disease ,Blastocyst ,Treatment Outcome ,Reproductive Medicine ,Infertility ,Female - Abstract
Chromosomal mosaicism, or the co-existence of cells with different chromosomal content, is a phenomenon that has been documented in human embryos for three decades. Early versions of preimplantation genetic testing (PGT-A) did not measure mosaicism, either because typically only a single cell was assessed, or because the technique could not accurately identify it. While this led to a straightforward diagnosis (an embryo was considered either normal or abnormal), it simply avoided the matter and in hindsight may have led to numerous misdiagnoses with negative clinical consequences. Modern PGT-A evaluates a multicellular biopsy with technologies capable of recognizing intermediate copy number signals for chromosomes or sub-chromosomal regions. We are therefore inevitably confronted with the issue of mosaicism and the challenge of managing embryos producing such results in the clinic. Here we discuss recent data showing that not only mosaicism in general, but specific features of mosaicism detected with PGT-A are associated with variable clinical outcomes. The conclusion is evident: mosaicism should be considered for more informed and improved embryo selection in the clinic.
- Published
- 2021