The CMG’s non-invasive prenatal testing (NIPT) test estimates the chance that a fetus is affected with Down’s syndrome (Trisomy 21), Edwards’ syndrome (Trisomy 18) or Patau’s syndrome (Trisomy 13) by analysing pieces of cell-free DNA (cfDNA) isolated from a sample of the mothers’ blood. In each of these syndromes the fetal DNA will include an extra copy of the chromosome concerned (e.g. in Down’s syndrome three chromosomes of chromosome 21 are found rather than the two expected to be found in an unaffected fetus). The CMG’s NIPT test is the first complete CE-IVD product for labs wishing to offer their own in-house non-invasive prenatal testing (NIPT) service.
The NIPT test looks for placental cell-free DNA isolated from the mother’s blood.
- During pregnancy a small amount of cfDNA leaks from the placenta into the mother’s bloodstream
- A small blood sample (10 ml) is taken from the mother’s arm
- Plasma is isolated from the mother’s blood which will contain a mixture of the mother’s and placental cfDNA
- If a fetus is affected by Down’s syndrome there will be more chromosome 21 in the circulating placental cfDNA
Therefore by counting the target chromosomes in the circulating cfDNA it is possible to determine if the fetus is likely to be Down’s affected; likewise for Edwards’ syndrome where there will be more chromosome 18 and Patau’s syndrome where there will be more chromosome 13 present.
Who can have NIPT test?
If you are at least 10 weeks pregnant with either a single or twin pregnancy you can have the NIPT test.
The NIPT test cannot be performed if the mother has cancer or Down’s Syndrome.
The NIPT test has an accuracy rate of >99% for trisomies 21, 18, 13 and >97% for sex determination. However, this accuracy can be affected if you have recently undergone a blood transfusion, transplant surgery, immunotherapy or stem cell therapy prior to the blood sample being taken. The NIPT test does not detect sex chromosomal abnormalities. If sex chromosomal abnormalities are present the accuracy of the sex determination may be compromised.Sex determination is not currently available for twins.
The NIPT test should be considered a screening test only. It is recommended that you discuss the results with your healthcare provider and that a positive result (i.e., a high chance of Down’s, Edwards’ or Patau’s syndrome being present) is considered along with other clinical screening results and may be followed up with an invasive procedure (i.e., Amniocentesis or CVS).
For further information please contact:
Tel.: (+374 10) 544367
Fax: (+374 10) 544366