Karyotype FetalDNA, which in other commercial tests is represented as “Kario” or “EKario” or “Cario”, represents a recently introduced NIPT, which investigates, always as screening, as well as on the chromosomal alterations researched in the test NIPT Basic FetalDNA also on all other numerical alterations, called aneuploidies, (alterations of the number only) of all the other chromosomes. In other words, it searches for the existence of an altered number of all 23 chromosomes.
The test is a screening that investigates not only fetal chromosomal aneuploidies related to autosomes 21, 18, 13 and X, Y sex chromosomes ,but also leads to the examination all the other chromosomes as happens in the study of the classic Fetal Karyotype. Obviously it also determines fetal sex which, on request, can be omitted.
Every individual has 2 copies of each chromosome and the term aneuploidies refers to numerical anomalies of the chromosomes. The term TRISOMY means that, for that particular chromosome, 3 copies, rather than 2, of that chromosome are observed. The term MONOSOMY means that, for that particular chromosome, 1 copies, rather than 2, of that chromosome are observed. The aneuploidies studied by Basic Plus FetalDNA are the most important and common that can affect the fetus.
TRISOMY OF CHROMOSOME 21 is the most common aneuploidy and refers to the presence of an extra copy of chromosome 21.
This syndrome is known as Down syndrome and represents, with an incidence of about 1/650 births, the most common form of intellectual disability.
TRISOMY OF CHROMOSOME 18 is the second most common aneuploidy and refers to the presence of an extra copy of chromosome 18. This syndrome is known as Edwards syndrome and is associated with a high abortion risks. Its incidence is estimated to be present in about 1/5000 births.
TRISOMY OF CHROMOSOME 13 is caused by an extra copy of chromosome 13 and is also known as Patau syndrome. It is associated with a high abortion; Newborns havedifferent pathological conditions that often cause deaths in childhood. It is estimated to have an incidence of about 1/16000 births.
SEX CHROMOSOME ANEUPLOIDIES are anomalies affecting the XY sex chromosomes and which can cause difficulties of language, motor and/or learning in the affected newborns. The most common of this class of aneuploidies is TURNER SYNDROME or X-LINKED MONOSOMY that affects women with only one copy of the X chromosome and has an incidence of about 1/2700 births. Other aneuploidies found with FetalDNA are X-chromosome trisomy (XXX), Klinefelter syndrome, and Jacobs syndrome.
And also, as already mentioned, thanks to the particular elaborate bioinformatics evaluation, it goes to explore ALL THE OTHER ANEUPLOIDIES OF ALL THE OTHER CHROMOSOMES.
Reporting times are included within 5 working days but may increase in case of technical difficulties on DNA analysis or if the test should be repeated.
N.B. Although FetalDNA tests provide maximum diagnostic accuracy today achievable with maternal blood screening methodologies, as is clear in the informed consent, no prenatal non-invasive testing (NIPT), regardless of methodology and the company that produces and markets it, provides, according to the current Guidelines, the insights related to the screening of sex chromosomes, all the other chromosomes, microdeletions/microduplications and fetal monogenic diseases.
It is therefore correct to inform that no widespread and commercialized NIPT tests can guarantee a sufficient degree of accuracy in relation to the genetic problems mentioned above. To this end, it reiterates once again the existence of sufficient scientific guarantees that can validate the clinical use of information related to the search for pathologies of sex chromosomes, of the other 22 autosomes, of microdeletions/ Microduplications and fetal monogenic diseases.
Therefore, subject to such research, the pregnant woman must be aware that all scientific literature and national and international Guidelines stipulate that only prenatal invasive diagnosis (Amniocentesis or CVS Test) represents the diagnostic test for such investigations.
If the mother has the Rhesus negative factor (documentable and visible at the time of FetalDNA’s request), it is possible to request a free analysis of the fetal Rhesus.
It may be specifically required not to become aware of fetal sex.