Non-invasion Prenatal Test
Harmony Prenatal Test - A new DNA-based blood test for Down’s syndrome.
Harmony Prenatal Test - A new DNA-based blood test for Down’s syndrome
This is a new DNA-based blood test for Down’s syndrome. It is more accurate than traditional tests and can be performed as early as 10 weeks in pregnancy.
The Harmony Non-invasive prenatal test analyses cell-free DNA circulating in the pregnant mother’s blood. It is a new option in prenatal screening for Down’s syndrome (trisomy 21) and two other chromosomal conditions, Edward’s syndrome (trisomy 18) and Patau syndrome (trisomy 13), X and Y chromosome conditions. This test can be requested for any singleton or twin pregnancy, including those conceived naturally or by IVF using the patient’s own egg or a donor egg.
Please note that sex chromosome (X and Y) analysis is not available for twin pregnancies.
About the Ariosa Harmony™ Prenatal Test
DNA from the fetus circulates in the mother’s blood. Cell-free DNA (cfDNA) results from the natural breakdown of fetal cells (presumed to be mostly placental) and clears from the maternal system within hours of giving birth. During a pregnancy, cfDNA can be tested to give the most accurate screening approach in estimating the risk of a fetus having a common chromosome condition sometimes called a trisomy. This occurs when there are three copies of a particular chromosome instead of the expected two.
The test looks to detect the following:
Trisomy 21 (Down’s syndrome) is the most common trisomy at the time of birth. It is associated with moderate to severe intellectual disabilities and may also lead to digestive disease, congenital heart defects and other malformations.
Trisomy 18 (Edwards syndrome) and Trisomy 13 (Patau syndrome) are associated with a high rate of miscarriage. These babies are born with severe brain abnormalities and often have congenital heart defects as well as other birth defects. Most affected individuals die before or soon after birth, and very few survive beyond the first year of life.
Sex chromosome conditions. The sex chromosomes (X and Y) determine whether we are male or female. X and Y chromosome conditions occur when there is a missing, extra, or incomplete copy of one of the sex chromosomes. The Harmony with X, Y test can assess risk for XXX, XYY, XXYY, XXY (Klinefelter syndrome), and a missing X chromosome in a girl (Turner syndrome). There is significant variability in the severity of these conditions, but most individuals have mild, physical or behavioural features. If the mother is interested in having this optional testing, she should talk with her healthcare provider to determine if it is right for her. This option is not available for twin pregnancies.
