Unique understanding of genetic disorders
Comprehensive genome sequencing to advance diagnosis
While both whole exome sequencing (WES) and whole genome sequencing (WGS) interrogate all genes in the human genome, WGS is more comprehensive in the variant classes it can identify. This type of genetic diagnosis allows for tailored medical management and treatment guidance for patients. Studies have shown that around 20% of patients had direct changes to care based on WES or WGS results.
Mayo Clinic Laboratories’ WGS test utilizes next-generation sequencing to interrogate nearly every base pair of an individual’s DNA, including the mitochondrial genome.
WGS is one of the most comprehensive and cost-effective genetic testing methods for patients with clinical features that do not fit within one disorder, or for patients with a suspected genetic disorder that could have many underlying genetic causes. WGS is recommended for patients with one or more congenital anomalies, developmental delay, intellectual disability, or a suspected underlying genetic condition. While both WES and WGS are exploratory tests that interrogate all genes, WGS is more comprehensive in the variant classes it can identify. WGS can detect variants in the non-coding region of DNA, certain spinal muscular atrophy variants, repeat expansions, and mitochondrial variants, potentially avoiding the need to order additional testing.
By the numbers
Up to 65%
21–65% of patients had direct changes to care based on WES or WGS results; higher likelihood of impact dependent upon timing of testing and patient population1,2,3
16 - 56%
16–56% diagnostic yield overall; higher yields experienced when WGS is used as a first-tier test or in cohorts with specific phenotypes1,2,3,4,5
Up to 30%
7%–30% increased diagnostic yield with WGS after prior negative test result, including whole exome sequencing2,5,6
Finding answers for patients
As a first-tier test for diagnosing hereditary disorders, WGS detects single nucleotide variants, small insertions and deletions, copy number variants, mitochondrial genome variants, and select spinal muscular atrophy and repeat expansion variants, throughout the genome. The information provided by this test can provide:
Whole genome sequencing streamlines diagnosis
Nicole Boczek, Ph.D., and Sarah Barnett, M.S., CGC, explain how Mayo Clinic Laboratories' whole genome sequencing provides comprehensive information for rapid diagnosis of hereditary disorders.
Improving the value of testing
Mayo Clinic Laboratories’ approach to whole genome sequencing includes gathering samples from biological parents of affected individuals, when possible, to compare and contextualize test results. These comparator specimens assist with result interpretation and increase the diagnostic yield of the testing. Each WGS order is carefully reviewed by a team of genetic counselors who ensure the indication for test ordering is clinically appropriate.
Beyond the test result
Mayo Clinic Laboratories’ WGS 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. WGS 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.