In case of a spontaneous fetal loss (recurrent or not) or of a voluntary interruption of pregnancy due to the presence of congenital anomalies incompatible with life, the conduction of a genetic study is indicated with the aim to determine the presence of genetic alterations responsible for the clinical case, and that may have repercussions in future pregnancies.
In these cases, the analysis by aCGH improves the detection rate and is an excellent alternative to conventional cytogenetic karyotype because NO growing cells are required, and the technique is therefore it is not affected by low cell viability, which causes the preparation of chromosomes to fail in a high percentage of cases.
qChip® PDC is an oligonucleotide microarray that interrogates the presence of copy number variants of complete chromosomes (aneuploidies), chromosomal regions associated with recurrent genomic disorders, subtelomeric and pericentromeric regions. Additionally, it also covers the rest of the genome with a lower probe density (1 probe / 125Kb, approx).
When is it indicated?
- Misscarriage or spontaneous fetal loss (recurrent or not).
- Legal pregnancy termination due to ultrasonographic findings.
- Concluded pregnancy with an anomalous karyotype that requires molecular characterization.
Please note that
In some cases, in order to complete study and understand the results to provide adequate genetic counseling, it may be necessary to carry out complementary studies (FISH, for example), both in the index case and in samples of other relatives (parents usually).
Technical details
- Chip with ~ 60,000 oligonucleotide-type probes.
- Interrogates 250 + known genetic syndromes (see link with list of diseases)
- Average coverage in clinically relevant regions: 1 probe / 10Kb.
- Average coverage in the rest of the genome: 1 probe / 125Kb.
Turn-around time: 15 working days from sample reception.
This design allows to
- Detect and characterize genetic alterations of submicroscopic copy number.
- Characterize imbalances of copy number previously identified with the karyotype study (deletions, apparently balanced translocations, additions, derivative chromosomes, etc.)
- Identify and characterize small supernumerary marker chromosomes (sSMCs) with euchromatic content (Tsuchiya 2008 Muy Cytog; Sheth 2011 EJMG).