Whole Exome Sequencing (WES)

It may be considered for children and adults with a suspected genetic disorder. It may be particularly useful in cases of developmental delay, intellectual disability, congenital anomalies, unexplained neurological findings, or suspected inherited kidney or heart disease. It may also be useful for patients whose previous tests have not provided a diagnosis. Suitability is determined based on clinical findings and family history.

A gene panel focuses on selected genes associated with a specific disease or group of diseases. WES examines the protein-coding regions of genes more broadly. Whole Genome Sequencing (WGS) evaluates both coding and non-coding regions of DNA. The most appropriate test is selected according to the condition being investigated.

WES alone does not diagnose autism, schizophrenia or bipolar disorder. However, it may help investigate an underlying genetic condition, particularly when developmental delay, intellectual disability, congenital anomalies or unusual clinical findings are also present. It is not a test that needs to be performed routinely for every psychiatric patient.

Solo WES examines only the patient; Duo WES examines the patient and usually one biological parent; Trio WES examines the patient and both biological parents together. Comparing family samples may help determine whether identified changes are inherited or have arisen for the first time in the individual, and may aid interpretation of the results.

An EDTA blood sample taken from the arm is generally used. For Trio analysis, separate samples are also collected from the mother and father. The shared Eurofins Biomnis brochure indicates approximately 4 weeks for a detailed report; sample shipping and additional investigations may extend the total turnaround time. Clinical information, previous test results and family history should also be shared with the laboratory to ensure accurate interpretation.

Identifying a disease-causing change that explains the patient's findings may support or confirm a genetic diagnosis. A negative result does not completely rule out a genetic disorder. A “variant of uncertain significance” (VUS) is a change whose association with disease is not yet clear; on its own, it is insufficient for a definitive diagnosis or treatment decision. Results should be evaluated with genetic counselling.

No. WES may not detect certain genetic changes, repeat expansions or changes in non-coding regions. The scope of chromosomal copy number variation (CNV) analysis and other additional analyses varies depending on the method used; other tests may be required. Reanalysis of existing WES data may be useful when new scientific knowledge or new clinical findings become available.

For some conditions, identifying the genetic cause may change the monitoring and treatment plan; however, not every result directly leads to a treatment. Pharmacogenetic analysis related to drug metabolism may be offered as a separate or additional assessment and should not be assumed to be automatically included in a standard WES report. In addition, the investigation and reporting of health findings unrelated to the reason for testing should be discussed as part of the consent process before the test.

No. Although WES tests share the same name, they may differ in how well genes are sequenced, which genetic changes are investigated and how results are interpreted. Looking only at the number of genes examined is not enough. Sequencing quality, the scope of additional analyses, expert assessment, the use of the patient's clinical information and the ability to reanalyse data when needed are important. Therefore, when choosing a test, both the price and the scope of analysis and reporting should be considered.

Eurofins Biomnis may be a preferred choice because of its ISO 15189-accredited laboratory infrastructure, experience in genetic analysis and approach to interpretation in collaboration with the clinician. According to the shared technical information, approximately 98% of targeted gene regions are examined at a sequencing depth greater than 30-fold. This means that DNA regions are read repeatedly to support the quality of the analysis.

The SeqOne bioinformatics platform enables genetic findings to be assessed alongside the patient's symptoms and family history. The ability to reanalyse existing data when needed and the provision of secure access to raw data are also important advantages. The aim is to turn genetic data into meaningful information that can be used in the patient's diagnosis and follow-up.

For information about WES testing and sample collection, you can contact the Wellcare Laboratories branches at Wellcare Health Clinic and Miracle Hospital in Nicosia, and at Medicalport Tunççevik Hospital in Kyrenia. The price varies depending on the choice of Solo, Duo or Trio testing, the scope of interpretation and additional analyses. The appropriate test and current turnaround time are assessed before proceeding.