examination of oocytes (polar bodies) or embryos (at the stage of fragmentation or blastocyst) in order to detect hereditary pathologies and chromosomal abnormalities. It is produced through DNA analysis. There are several types of PGT depending on the goals:
1) PGT-A (for aneuploidy) – detects a change in the number of chromosomes.
2) PGT-M (monogenic preimplantation genetic testing) – helps to identify monogenic mutations, that is, disorders affecting individual genes.
3) PGT-SP (for structural rearrangements) – it is used to detect changes in the structure of chromosomes: deletions (loss of sections), duplications (doubling of sections), inversions (rotation of a region by 180 degrees), translocations (exchange of fragments between chromosomes).