Genetic Testing

Genetic Testing

Genetic testing looks for changes, sometimes called mutations or variants, in DNA. Genetic testing is helpful in many areas of medicine and can change the medical care that a person or his/her family member receives.

Birth defects, which occur in nearly one in 20 pregnancies, range in severity from minor anatomic abnormalities to extensive genetic disorders or mental retardation. Some couples have a greater than average risk of having a child with a birth defect. Genetic screening refers to the use of specific tests to determine which members of a population are at increased risk for an inherited condition. Genetic testing, in contrast, is the use of specific tests to characterize the genetic status of an individual who is suspected to be at increased risk for an inherited disease. Genetic screening may help identify couples who have an increased risk of age-related or familial genetic disorders and birth defects.

Genetic testing is an important procedure to consider before IVF treatment.

No single test, however, can accurately predict the risk of all defects in a child, and many birth defects, such as those related to environmental and toxic exposures and those that are random and unexplained, are not genetically based and may not be detected with genetic screening.

Reasons for Genetic Testing
  • To learn whether you have a genetic condition that runs in your family before you have symptoms
  • To learn about the chance, a current or future pregnancy will have a genetic condition
  • To diagnose a genetic disorder if you or your child has symptoms
What is Preimplantation Genetic Testing (PGT)?

Preimplantation genetic testing (PGT) is a technique in which one or more cells are taken from an egg or embryo (fertilized egg) for testing to have information about the genetic make-up of the embryo. It is done in a lab and used in conjunction with in vitro fertilization (IVF).

PGT is divided in two categories:

  1.  Preimplantation Genetic Screening (PGS)
  2. Preimplantation Genetic Diagnosis (PGD)

However, leading medical societies focused on reproductive health (including ASRM – American Society for Reproductive Medicine and ESHRE -European Society of Human Reproduction and Embryology) have come together and by the end of 2018 new names have been published for PGS and PGD to more accurately represent and standardize the terminology for the fertility experts around the world.

Current Name New Name
PGS (Preimplantation Genetic Screening) PGT-A (Preimplantation Genetic Testing for Aneuploidies)
PGD (Preimplantation Genetic Diagmosis) fpr Single Gene Disorders PGT-M (Preimplantation Genetic Testing for Monogenic/Single Gene Defects)
PGD (Preimplantation Genetic Diagnosis) for Chromosome Rearrangements PGT-SR (Preimplantation Genetic Testing for Chromosomal Structural Rearrangements)