Brand-new varvis® use case
How to Perform Carrier Screening Using the varvis® Software
Carrier screening enables the analysis of two unaffected individuals who might be carriers of disease-causing variants. Here we will show how these variants can quickly be identified in varvis® even for expanded carrier screening tests.
What is Carrier Screening?
According to the American College of Obstetricians and Gynecologists (ACOG), carrier screening describes genetic testing that is performed on an individual who does not have any overt phenotype for a genetic disorder but may have one variant allele within a gene(s) associated with a diagnosis. Carrier screening tests are usually performed pre-conception or during pregnancy in order to determine the risk of having a child with certain recessive genetic disorders. Examples of autosomal recessive disorders include cystic fibrosis, sickle cell anemia, and Tay-Sachs disease. The carrier rates of the individual diseases vary significantly depending on the ethnicity of different sub-populations.
Targeted vs Expanded Carrier Screening
Targeted carrier screening is typically performed at high-risk populations, such as screening individuals of Ashkenazi Jewish descent for Tay–Sachs disease. This approach is pretty straight forward and results can be interpreted easily. In contrast, expanded carrier screening evaluates an individual’s or couple’s carrier state for multiple conditions at once and regardless of ethnicity. This very broad approach can be challenging in terms of variant interpretation, as usually many candidate variants are detected on many candidate genes that have to be evaluated carefully, and the carrier status of two separate individuals has to be considered with respect to each other.
How is it performed in varvis®?
Imagine a couple who came in for carrier screening analysis. Expanded NGS analysis has been performed for both and raw sequencing data has automatically been processed by the varvis® bioinformatics pipeline. Carrier screening analysis can now be performed in the varvis® software in three easy steps:
- Link the individuals as partners.
- Indicate that both are unaffected individuals.
- Open the overview of all detected variants and click the carrier screening filter.
This filter will reduce the list to those variants where both partners have a heterozygous variant call in the same gene and would therefore facilitate identifying variants in the paternal and maternal alleles for a recessive disorder. It can be combined with other filter buttons that are readily available in the variant table, e.g. filter for variants that are rare in gnomAD or with high/moderate putative impact on protein level.
See for yourself
If you want to learn more about the varvis® services, please get in touch with us to request more information and your personal varvis® software demo.
About varvis®
varvis® is a clinical decision support system designed by Limbus Medical Technologies GmbH, a medical device manufacturer and software development company. The cloud-based genomics platform is tailored to support the entire NGS workflow, from raw data processing, to genomics data management and variant interpretation. Automated CNV and SNV analysis are completely integrated into the NGS workflow and clinically validated for panels of all sizes including WES. Our services comprise first class support, training, automated quality control and validation compliant with relevant international guidelines. varvis® is a registered CE-IVD device and specifically made to aid in the diagnosis of patients.
