There are three types of PGT services available which we have briefly discussed below:
I. PGT – A
Preimplantation Genetic Testing for Aneuploidy (PGT-A) previously known as Preimplantation Genetic Screening (PGS) is a genetic test to identify and transfer euploid (chromosomally normal) embryos by screening all 23 pairs of the human chromosome for aneuploidy.
Embryos having an incorrect number of chromosomes may lead to unsuccessful pregnancy or the baby being born with a genetic condition such as Down’s syndrome, Turner’s syndrome, etc.
II. PGT – M
Preimplantation Genetic Testing for Monogenic (single-gene) disorders (PGT- M) previously known as Preimplantation Genetic Diagnosis (PGD) is used to test embryos of couples with a high risk of passing a known inherited genetic disorder caused by mutations in a single gene, such as Sickle cell anaemia, Cystic fibrosis Beta-thalassemia, Huntington’s disease etc.
III. PGT – SR
Preimplantation Genetic Testing for Structural Rearrangements (PGT-SR) was initially known as Preimplantation Genetic Diagnosis for chromosomal translocation. This method identifies embryos with the correct amount of genetic material and embryos having extra or missing genetic material due to the translocation or rearrangement (unbalanced).
PGT-SR reduces the risk of having a child with an unbalanced structural abnormality, which may result in a pregnancy loss.