D.U.K.

This is a genetic blood test, during which circulating fetal DNA is isolated from the mother's blood plasma, in which, with the help of next-generation sequencing and bioinformatics analysis of the obtained data, changes in the genetic material of the fetus are searched for.

The NIPT test is non-invasive, so there is no risk to the mother and fetus.

Non-invasive prenatal testing is suitable both after natural conception and after an in vitro fertilization procedure, which is considered an increased risk factor for fetal abnormalities.

Only the venous blood of the pregnant woman is taken for the test to determine the genetic diseases of the fetus, so the biological father cannot be determined with this test.

VeriSeq^TM NIPT Solution v2 test can be performed from the 10th week of pregnancy until the end of pregnancy.

The test is applied only for singleton and twin pregnancies. The test is not suitable for detecting polyploidy, such as triploidy and balanced chromosomal rearrangements (translocations). The examination is performed no earlier than the 10th week of pregnancy (10+0).

Results may be affected by:

• recent maternal blood transfusion;
• the mother underwent an organ transplantation/stem cell transplantation;
• maternal autoimmune diseases;
• benign and malignant tumors of the mother;
• maternal mosaicism;
• maternal copy number variation (CNV);
• placental mosaicism.

Saide Genomics performs four types of NIPT tests: N3, N4, N5 and N6.

N3 NIPT test used to determine the risk of chromosomal aneuploidies that may affect the health of the fetus: Down syndrome (trisomy 21), Edwards syndrome (trisomy 18) and Patau syndrome (trisomy 13). In addition to the mentioned trisomies, when the pregnancy is singleton, the risk of sex chromosome aneuploidies can be additionally investigated: Turner syndrome (45,X), Klinefelter syndrome (47,XXY), XXX and XYY (N4 NIPT test). The NIPT test also has the ability to determine the risk of partial deletions and duplications of 7 Mb or larger (N5 NIPT test) and the risk of all remaining autosomal aneuploidies (N6 NIPT test).

NIPT test results are available within 2-7 business days after the blood sample is delivered to the laboratory. If the test needs to be repeated, the response may be delayed.

Aneuploidy - an altered set of chromosomes, when one or more chromosomes from the normal set of chromosomes are absent (monosomy) or there are additional copies of them (trisomy, etc.), for example, Down syndrome (three copies of the 21st chromosome instead of two), Edwards syndrome ( three copies of chromosome 18 instead of two), Patau syndrome (three copies of chromosome 13 instead of two), Turner syndrome (one sex chromosome X instead of two XX), etc.

The risk that the fetus will have Down's, Edwards', Patau's syndromes, Turner syndrome and other disorders of the number of sex chromosomes and other chromosomal abnormalities is low. NIPT testing cannot detect chromosomal mosaicism, polyploidy, or rare monogenic diseases. However, having a low risk of chromosomal disease does not guarantee that the fetus will not have other abnormalities in fetal development that can be seen on ultrasound, such as brain, heart or spine abnormalities.

The fetus has a high risk of Down, Edward, Patau syndromes, sex chromosomes, autosomes, partial deletions or duplications. Since NIPT is a screening test, definitive pregnancy decisions cannot be made based on the NIPT result alone. An invasive diagnostic test, such as amniocentesis, should be considered with a geneticist to confirm the diagnosis. Amniocentesis may reveal that the genetic change detected by NIPT is specific to the fetus itself (confirmation of the diagnosis), or that the fetus is healthy but the change belongs to the placental tissue (so-called placental mosaicism) - this is also a significant result, as placental mosaicism can lead to delayed development of the fetus in the womb, certain birth complications, etc.

During the NIPT test, the gender of the fetus is determined based on the free fetal DNA circulating in the pregnant woman's blood. If the Y chromosome is detected, the fetus is male, if the Y chromosome is absent, the fetus is female. In very rare cases, the sex of the fetus cannot be determined. One of the possible reasons is a twin pregnancy, where one of the twins is vanishing. In this case, it is possible that one of the fetuses is developing (female), but traces of the Y chromosome of the dead fetus (male) are still found in the mother's blood.

Free DNA fragments of both the mother and the developing fetus circulate in the mother's blood. The fraction of fetal/placental DNA fragments is called the fetal DNA fraction. Circulating free fetal DNA averages 10% of circulating maternal DNA, and its amount (fraction) increases progressively during pregnancy. A low fraction of fetal DNA (<3-4%) increases the chance of NIPT failure.

If the NIPT test fails, the test result cannot be provided. Such a test result can be determined by inappropriate blood sample collection, transportation or technical limitations, as well as individual physiological factors of the pregnant woman. After receiving an uninformative result, the Saide Genomics laboratory gives the patient the opportunity to perform the test again. One retest is free. If, after repeating the test, the answer is the same, depending on the possible reason for the failed test, consultation with a geneticist is recommended, who, if necessary, can order additional diagnostic genetic tests.

In order to confirm the diagnosis or make other decisions related to pregnancy, you cannot rely solely on the results of this test, it is necessary to consult with the doctor supervising the pregnancy. A positive test result requires consultation with a geneticist who may order additional diagnostic genetic tests, such as amniocentesis (amniotic fluid test) or chorionic villus biopsy, to confirm or deny a fetal chromosomal abnormality or other genetic disease.