Prenatal testing

Non-invasive Prenatal Testing (NIPT)

Missing or extra copies of chromosomes are called aneuploidies. Trisomies occur when three, instead of the usual two, copies of a chromosome are present in a person’s genetic make-up. The most common trisomies involve Chromosomes 13, 18 and 21, which are associated with Patau syndrome, Edward syndrome, and Down syndrome, respectively. Aneuploidies of the sex chromosomes (X and Y) can also cause genetic conditions, including Turner syndrome (having only single X chromosome), Trisomy X (XXX), Klinefelter syndrome (XXY) and Jacobs syndrome (XYY).

Non-invasive prenatal testing (NIPT) is careening tool used to quantify the DNA of an unborn baby in order to determine whether it has any missing or extra copies of Chromosomes 13, 18 and 21, as well as the sex chromosomes. A blood sample is obtained from a pregnant mother from as early as 10 weeks of estimated gestational age, from which the unborn baby’s DNA is obtained (called cell-free foetal DNA). Sequencing technology is used to count the number of copies of these chromosomes, and a calculation method is used to determine whether there are any missing or extra copies.





Genesis Genetics is a leading global provider of Preimplantation Genetic Diagnosis and Screening (PGD/PGS) – providing expert laboratory services for many of the most respected in vitro fertilisation (IVF) centres across the country and throughout the world.

Contact details:

Dr Jaysen Knezovich
Laboratory Director &
Medical Scientist
Genesis Genetics SA
+27 (0) 11 784 5335