Now available from June 2019 for clinical diagnosis: a new diagnostic test focused on disease-specific epigenetic signatures: Episign
. EpiSign is performed on a peripheral blood sample and can analyze DNA methylation patterns of the genome to establish a diagnosis or help resolve variants of uncertain significance (VUS). Episign is performed as a collaboration of Amsterdam UMC, the Netherlands and London Health Sciences, Canada.
To date, combined efforts have identified unique methylation patterns, known as epigenetic signatures, for 21 genetic disorders including CHARGE syndrome, Cornelia de Lange syndrome, Down syndrome, Kabuki syndrome, Sotos syndrome, Williams syndrome, ATRX syndrome, autosomal dominant cerebellar ataxia with deafness and narcolepsy (ADCADN), BAFopathies (Coffin-Siris syndrome , Nicolaides-Baraitser syndrome, Chr6q25del), Claes-Jensen syndrome, Genitopatellar syndrome, Floating Harbor syndrome, ADNP-related syndrome/Hellsmoortel-VanDerAa syndrome, and Chr7q11.23dup.
“Current diagnostic technologies such as microarray and whole exome sequencing are not able to assess non-coding and more complex variants, and cannot provide information on epigenetic changes,” said Bekim Sadikovic, PhD, DABMG FACMG, Division Head, Molecular Diagnostics, LHSC; and Associate Professor, PaLM, Western University, who leads the epigenetic signature research. “This technology provides a new level of analysis beyond the genome.”
This test may be a useful screening tool for patients with developmental delay, or with one or more overlapping features suggestive of one of the represented epigenetic signature conditions or imprinting disorders.
Methylation abnormalties detected using this test may require additional targeted testing to confirm and further
characterize the underlying genomic abnormality. This test will not detect females with Fragile X (FMR1) expansions.
4-6 ml of peripheral blood collected in an EDTA (lavender top) tube is the required specimen type. The minimal blood needed for reliable DNA isolation is 3 ml. Extracted DNA or banked is also accepted for this test given the original specimen was whole blood collected in an EDTA tube.
The 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.