Our Tests / WES / Optima WES

Overview of Whole Exome Sequencing (WES)

Whole Exome Sequencing (WES) is a comprehensive genomic test that analyzes the protein-coding regions of the genome, known as exons, where the majority of clinically relevant genetic alterations (variants) are found. By examining thousands of genes simultaneously, WES enables the detection of genetic alterations associated with a wide range of inherited and de novo conditions. It is a powerful diagnostic tool that can be applied both prenatally, when fetal anomalies are identified or suspected, and postnatally in individuals with unexplained developmental, neurological, or multisystem disorders. Through its broad yet clinically focused approach, WES supports precise diagnosis, informed clinical management, and improved patient care.

Patient Information Clinician Information

Whole exome sequencing clinical consultation

What is Whole Exome Sequencing (WES)?

Whole Exome Sequencing (WES) is a comprehensive genetic test that analyzes the exons, the protein-coding regions of approximately 20,000 genes in the human genome. Although exons represent only a small portion of the genome, they contain the majority of known disease causing variants, making WES a powerful tool for investigating suspected genetic disorders in both prenatal and postnatal settings.

What does Whole Exome Sequencing (WES) screen for?

WES is used to identify genetic variants associated with a broad range of inherited and de novo disorders. It is particularly valuable when a condition may be caused by one of many different genes, including neurodevelopmental, neurological, metabolic, syndromic, and multisystem disorders. In prenatal care, it may also be considered when fetal structural anomalies are detected and standard genetic testing has not provided an explanation.

Why choose Whole Exome Sequencing (WES)?

WES offers a broad yet clinically focused approach when symptoms or ultrasound findings do not clearly indicate a single diagnosis. By assessing thousands of genes at once, it can help shorten the diagnostic journey, improve clinical decision-making, support prognosis and recurrence-risk counseling, and guide next steps for patient management or future reproductive planning.

How is Whole Exome Sequencing (WES) different?

Unlike targeted gene panels, which assess a selected group of genes linked to a specific condition, WES examines the coding regions across nearly all clinically relevant genes in a single analysis. At the same time, it is more focused than Whole Genome Sequencing (WGS), which extends beyond coding regions into the noncoding genome. This makes WES a strong option when a broad search is needed while maintaining emphasis on the region’s most commonly associated with disease.

Who can consider Whole Exome Sequencing (WES)?

WES may be considered for fetuses with unexplained structural abnormalities, for newborns or children with developmental delay, congenital anomalies, seizures, or suspected rare disease, and for adolescents or adults with complex clinical presentations that remain undiagnosed after prior evaluation. It is especially useful when previous testing has been negative or when the phenotype does not clearly match a single disorder.

What to expect?

The process typically begins with clinical review and genetic counseling to determine whether WES is appropriate. Testing usually requires a DNA sample, commonly from blood for postnatal referrals and amniotic fluid for prenatal referrals, and in many cases trio analysis including biological parents may improve interpretation. Results may identify a pathogenic or likely pathogenic variant, may be negative, or may reveal a variant of uncertain significance (VUS). Because WES is a highly informative but complex test, results should always be interpreted in the context of the patient’s clinical findings and family history.

Is OPTIMA WES test right for you?

We're here to help you find out.