What Does Carrier Screening Find?
Most people can be carriers of a disease causing change without knowing it. If both partners are carriers, they have a 25% risk of having an affected child with a recessive genetic disease and a 50% that the child will be a carrier like the parents.
Getting tested early gives future parents the opportunity to make informed decisions and review the range of options available to guide pregnancy and family planning.
The CentoScreen® Advantage
Why choose CentoScreen® for your patients?
- Sequencing of coding regions +/- 20 flanking intronic bases of 331 genes
- Integrated copy number variation (CNV) reporting for 34 genes
- Includes most relevant disease-causing variants from HGMD® 2017.4, including deep intronic variants, and proprietary
- CentoMD® variants
- Additional analyses for fragile X syndrome, spinal muscular atrophy, and congenital adrenal hyperplasia (FMR1, SMN1 and CYP21A2 genes respectively)
- ≥99% of targeted genes covered at ≥ 20x sequenced by next generation sequencing
- Confirmation of low quality SNPs by Sanger sequencing and all CNVs by qPCR or MLPA prior to reporting
Who can be offered carrier screening with CentoScreen®?
CentoScreen® can be offered to individuals considering a pregnancy or in early pregnancy. It is appropriate for individuals or couples with the following backgrounds:
Based on previous analyses of several tens of thousands of cases, CENTOGENE has defined quality criteria for single nucleotide variants (SNVs), which when met, show 100% concordance with Sanger sequencing. Therefore, for SNVs that meet our quality parameters, NGS approaches the same level of validity as Sanger sequencing and additional Sanger sequencing does not provide any additional information.
However, the following variants if chosen for reporting are always confirmed by an orthologous method:
• SNVs that do not meet our quality thresholds – by Sanger sequencing
• All indel variants (small insertions and deletions causing frameshift mutations) – by Sanger sequencing
• Copy number variations (CNVs) – by microarray, MLPA or qPCR
The panel includes FMR1 repeat expansion analysis which can determine the risk having a child with Fragile X syndrome. However, fragile X syndrome is XLD and either parent could have an expansion in the permutation range that, if transferred to the child could be causative for the syndrome. The way the paired pack analysis is set up, we can exclude that the initially tested partner transmits the possibly pathogenic allele, but since the initial or first partner would be negative we would not activate the analysis for the second partner. This means that we cannot completely assess the risk of passing on fragile X syndrome to their children. The clinician would need to order FMR1 separately or order the duo analysis to be absolutely sure.
No. As this is not a WES/CES/WGS.
No. The most important factor in a panel is choosing the right genes to screen for and the right methodology. As Centogene has both a large number of clinically relevant genes and a variant database to interpret the variants in all of the genes included in the panel, we offer the best package.
This is flexible. Both males and females can be tested first and is determined by the physician.
In such cases where there is no family history of genetic disease and both partners will be tested, testing the female sample first would be logical due to the assessment of X-linked disorders (males would, if carrying such variants, already be impacted as they only have one X chromosome).
We do not report ACMG incidental findings as this is not purpose of test. Additionally, this is a specially designed targeted carrier screening panel, not exome or CES-based, these genes are not on the panel.
However, for a few conditions patients themselves can be identified as being affected for diseases with mild presentation or late-onset forms (eg. Gaucher). Patients should be counselled accordingly and this information is also listed on our request form.
Yes. TAT is 14 business days for all testing options. Please keep in mind for CentoScreen® Paired X-TRA, the second sample would be sent after results for the first sample have been delivered to the customer. After the arrival of the second sample of CentoScreen® Paired X-TRA, the patient would need to wait an additional 14 business days.