Whole Exome Sequencing-XL, Reanalysis

Technical Information

Whole Exome Sequencing – XL (WES-XL) detects single nucleotide variants (SNVs) within exonic regions, intronic regions, promoters, and 3’-UTRs. SNVs are only detected in intergenic regions if the variant has been previously reported. WES-XL will detect copy number variants (CNVs). Disease-associated sequence variants in the mitochondrial genome will also be reported. WES-XL will not detect trinucleotide repeat expansions, methylation abnormalities, balanced rearrangements, and some small exonic-level copy number changes. Reanalysis can be ordered as a separate for an additional charge.

Specimen Requirements

• The preferred sample type is 3-4 ml of peripheral blood collected in an EDTA (purple top) tube. Extracted DNA and saliva are also accepted for this test.
• Blood and saliva kits are available by request.
• Send approximately 5µg of extracted DNA at a requested concentration of 90-130 ng/µl.
• Saliva samples must be submitted in an approved saliva kit.
• Saliva, saliva swabs, or extracted DNA from saliva samples may not meet the lab’s quality control threshold for sequencing on the genome platform. For saliva samples that do not meet QC standards, providers will be contacted to determine whether a new blood sample can be collected or if testing should be run on an exome platform instead. All FFPE samples will be run on an exome platform.

Transport Instructions

• The blood specimen should be kept at room temperature and delivered via overnight shipping. If shipment is delayed by one or two days, the specimen should be refrigerated and shipped at room temperature. Do not freeze the specimen. Samples collected on Friday can be safely designated for Monday delivery.
• Extracted DNA should be sent at room temperature via overnight delivery.
• Saliva is stable at room temperature and can be delivered via overnight or ground shipping.