Diagnostic Center for Heritable Immunodeficiencies
Laboratory News

News from the Diagnostic Center for Heritable Immunodeficiencies

Expanded Next-Generation Sequencing Panels  

We have recently expanded two of our immunodeficiency gene sequencing panels!  Our bone marrow failure gene sequencing panel has been enhanced with the addition of 49 genes related to bone marrow failure disorders.  This expansion includes sequencing for somatic level variants in TLR8.  Somatic variants are expected to be identifiable when they are present at an allele frequency greater than 5%.  We have also expanded our hemophagocytic lymphohistiocytosis (HLH) gene sequencing panel to 27 genes with the addition of nine genes associated with hereditary HLH.  Follow the links below for more information. Note: Any gene on the panels specified below may also be ordered individually as a Sanger-based sequencing test.

What Is Next-Generation Sequencing?

Next-generation sequencing (NGS) is a method of sequencing multiple genes at one time. Unlike traditional Sanger sequencing, NGS involves randomly fragmenting a patient's DNA, sequencing these fragments, and bioinformatically fitting the pieces back together.

NGS is more efficient and economical than Sanger sequencing if more than one or two genes are being tested at once. It is important to note that any genetic testing can result in uncertain findings (variants of uncertain clinical significance) and a test that sequences more genes will identify more of these variants. 

Which Is the Best Test? 

NGS panels that test multiple genes associated with a given phenotype are particularly valuable when a condition is suspected but the responsible gene is unknown. When a certain gene is strongly suspected, Sanger sequencing of that gene may be a better choice. When a specific mutation has been identified in a family, targeted mutation analysis is the best option.

To discuss testing strategies for a specific patient, call 513-636-4474 and ask to speak with a genetic counselor.