An overview of the current and emerging platforms for preimplantation genetic testing for aneuploidies (PGT-A) in in vitro fertilization programs

Hsin-Fu Chen; Ming Chen; Hong-Nerng Ho

doi:10.1016/j.tjog.2020.05.004

An overview of the current and emerging platforms for preimplantation genetic testing for aneuploidies (PGT-A) in in vitro fertilization programs

Taiwan J Obstet Gynecol. 2020 Jul;59(4):489-495. doi: 10.1016/j.tjog.2020.05.004.

Authors

Hsin-Fu Chen¹, Ming Chen², Hong-Nerng Ho³

Affiliations

¹ Department of Obstetrics and Gynecology, College of Medicine and the Hospital, National Taiwan University, Taipei, Taiwan; Graduate Institute of Medical Genomics and Proteomics, College of Medicine, National Taiwan University, Taipei, Taiwan; Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan. Electronic address: hfchen@ntu.edu.tw.
² Department of Medical Genetics, College of Medicine and the Hospital, National Taiwan University, Taipei, Taiwan; Department of Obstetrics and Gynecology, Changhua Christian Hospital, Changhua, Taiwan; Department of Genomic Medicine and Center for Medical Genetics, Changhua Christian Hospital, Changhua, Taiwan. Electronic address: mingchenmd@gmail.com.
³ Department of Obstetrics and Gynecology, College of Medicine and the Hospital, National Taiwan University, Taipei, Taiwan; Graduate Institute of Medical Genomics and Proteomics, College of Medicine, National Taiwan University, Taipei, Taiwan; Graduate Institute of Immunology, College of Medicine, National Taiwan University, Taiwan. Electronic address: hnho@ntu.edu.tw.

PMID: 32653118
DOI: 10.1016/j.tjog.2020.05.004

Abstract

Preimplantation genetic testing for aneuploidies (PGT-A) and PGT for monogenic disorders (PGT-M) have currently been used widely, aiming to improve IVF outcomes. Although with many years of unsatisfactory results, PGT-A has been revived because new technologies have been adopted, such as platforms to examine all 24 types of chromosomes in blastocysts. This report compiles current knowledge regarding the available PGT platforms, including quantitative PCR, array CGH, and next-generation sequencing. The diagnostic capabilities of are compared and respective advantages/disadvantages outlined. We also address the limitations of current technologies, such as assignment of embryos with balanced translocation. We also discuss the emerging novel PGT technologies that likely will change our future practice, such as non-invasive PGT examining spent culture medium. Current literature suggest that most platforms can effectively reach concordant results regarding whole-chromosome ploidy status of all 24 types of chromosomes. However, different platforms have different resolutions and experimental complexities; leading to different turnaround time, throughput and differential capabilities of detecting mosaicism, segmental mutations, unbalanced translocations, concurrent PGT-A and PGT-M etc. Based on these information, IVF staff can more appropriately interpret PGT data and counsel patients, and select suitable platforms to meet personalized needs. The present report also concisely discusses some crucial clinical outcomes by PGT, which can clarify the role of applying PGT in daily IVF programs. Finally the up-to-date information about the novel use of current technologies and the newly emerging technologies will also help identify the focus areas for the design of new platforms for PGT in the future.

Keywords: Comprehensive chromosome screening (CCS); In vitro fertilization; Preimplantation genetic testing (PGT); Preimplantation genetic testing for aneuploidies (PGT-A); Preimplantation genetic testing for monogenic/single gene disorders (PGT-M).

Publication types

Review

MeSH terms

Aneuploidy
Female
Fertilization in Vitro / methods*
Humans
Pregnancy
Preimplantation Diagnosis / methods*