Examples of next-generation sequencing: what to know

Next-generation sequencing reads many DNA regions in parallel. In cancer care, Genomic Tumour Profiling can examine tumour changes that may help a specialist consider treatment options. A Breast Cancer Gene Expression Test is another example of molecular information being used to support a specific clinical decision, although tests differ in what they measure.

Outside cancer care, Genetic Carrier Screening can look for inherited changes that a person may pass on without having the related condition. NIPT analyses pregnancy-related DNA in a blood sample, while PGT-A and PGT-M examine selected embryo material for different genetic questions. Pre-marital Screening may also use laboratory testing to assess inherited conditions.

Start by asking what health question the test is designed to answer and whether the sample comes from blood, tumour tissue, an embryo, or another source. The number of genes examined does not by itself determine whether a test is useful; interpretation depends on the condition, family history, sample quality, and clinical context.

Ask how findings are classified, whether uncertain findings are reported, and who will explain the result. Genetic counselling may be helpful when testing could affect relatives, reproductive choices, or future care. A sequencing result is not a diagnosis without appropriate clinical interpretation.

Sequencing is usually planned testing rather than an emergency procedure. Seek urgent medical care for symptoms such as severe breathing difficulty, collapse, heavy bleeding, or sudden neurological change; do not wait for genetic results. Contact the testing team if a result is delayed, confusing, or linked to a new symptom that needs assessment.

Which gene regions will be examined, and why? What can this test detect or miss? Could the result affect my relatives or reproductive decisions? Will a genetic counsellor review the findings, and what follow-up would an uncertain result require?