Preimplantation genetic applications are divided into two. The first and most used of these are applications called preimplantation genetic screening (PGS), which are used to reveal the structural and numerical disorders of chromosomes.
Preimplantation genetic diagnosis (PGD), on the other hand, is based on the recognition of diseases known to exist and inherited from a single gene. With a different technology called PCR, the change in the gene causing the disease is detected at the embryo level and unhealthy embryos are not transferred.