Individualized insights for personalized care
Advance understanding of genetic disease
For millions of individuals affected by rare disease — 80% of which are genetic in origin1 — knowing the underlying genetic cause is a critical first step in ending their diagnostic odyssey. Whole exome sequencing (WES) is recommended by the American College of Medical Genetics and Genomics (ACMG) as a first-line testing option to find underlying causes of rare genetic disorders in those who present with one or more congenital abnormalities or developmental delay and intellectual disability with onset prior to age 18.2
Mayo Clinic Laboratories’ whole exome sequencing test utilizes next-generation sequencing to investigate approximately 20,000 genes in patients with suspected hereditary disorders. Not only is WES recommended to identify genetic variants in individuals with congenital abnormalities, it is also recommended for patients with clinical features or family histories suggestive of underlying genetic disease but not distinguishable through other genetic tests.
By the numbers
50% of patients who underwent WES testing were clinically impacted3
36% of patients who underwent WES testing received genetic diagnosis4,5
18% of patients with diagnostic results from WES testing received alternate treatment recommendations6
Accurate answers, tailored management
Designed to detect single nucleotide variants, small insertions or deletions, deletion-insertions (delins), and copy number variants, our WES test’s precision provides answers that profoundly impact a patient’s medical journey.
Variant identification not only enables insight into which gene(s) might be causing the disorder but can offer important information for family members about their risk for inheriting the same condition. Results also enable medical management and treatment targeted toward a specific diagnosis. Moreover, answers can put to rest a patient’s search for a cause, ending the diagnostic odyssey.
Whole exome sequencing for hereditary disorders
Cherisse Marcou, Ph.D., co-director of the Clinical Genomics Laboratory, and Marissa Ellingson, M.S., CGC, laboratory genetic counselor, discuss whole exome sequencing at Mayo Clinic Laboratories. The comprehensive evaluation uses next-generation sequencing to detect for single nucleotide variants, small insertions or deletions, deletion-insertions, and copy number variants in approximately 20,000 genes, enabling precision answers to accurately diagnose, manage, and treat patients with identified inherited disorders.
Improving the value of testing
Mayo Clinic Laboratories’ approach to whole exome sequencing includes gathering samples from biological parents of affected individuals, when possible, to help compare and contextualize test results. These comparator specimens assist with result interpretation and increase the diagnostic yield of the testing. Each WES order is carefully reviewed by a team of genetic counselors who ensure the indication for test ordering is clinically appropriate. A diagnosis is identified in trio-based whole exome sequencing in approximately 25% to 37% of cases.4-6
Beyond the test result
Mayo Clinic Laboratories’ WES test is backed by a team of laboratory scientists, genetic counselors, and clinicians who are integrated into the clinical practice at Mayo Clinic. This collaboration allows for direct consultation with practicing clinicians in instances of complex or unclear cases. WES results are interpreted by a collaborative team who consider previous evaluations and test results from genetic studies, biochemical testing, and imaging studies as part of the genetic data review. Genetic disease experts are available to answer questions about test findings or the need for additional testing.