Genomic testing is commonly used in cancer treatment to determine how a tumor will likely behave.
Genetics
Genetics is the study of the effects that genes have on an individual.
Genes provide the body instructions on how to make proteins.
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Proteins determine the structure and function of each cell of the body.
Genes are made up of building blocks called DNA that are arranged in a string called bases.
The order, or sequencing, of bases will determine which instructions are sent and when.
Many genes are coded to make specific proteins.
Non-coded genes regulate how and when the proteins are made by turning on and off certain genes.
TheBRCA1 and BRCA2 mutationsare associated with breast and ovarian cancer.
Genetic tests can look for any genetic mutation you may have inherited from your parents.
They can confirm a diagnosis, predict future risk, or identify if you are acarrier.
The genetic material plus all of sequences are called thegenome.
Unlike genetics, genomics is not constrained to inheritable mutations.
By understanding these ever-changing variables, healthcare providers can make more informed choices in treatmentoften preemptively.
What Genomic Testing Is Used For
Genomic testing is based on current understanding of the human genome.
This process began with the collaborativeHuman Genome Projectfrom 1990 to 2003.
Scientists have been able to increasingly identify which genetic anomalies translate to the development and characteristics of a disease.
Genetic tests can confirm or rule out a suspected genetic condition.
The growing movement toward personalized medicine is changing how we approach diseases in general.
The tests are typically performed in a specialized lab certified under theClinical Laboratory Improvement Amendments (CLIA).
There are more over 500 CLIA-certified genetics labs in the United States.
Abiopsyof a tumor or bone marrow may be needed for people with cancer.
Once the sample is obtained, it usually takes between one and four weeks to receive the results.
Next-Generation Sequencing
Next-generation sequencing is the primary tool for genomic testing.
It identifies and evaluates the genetic sequence of millions of short DNA segments called reads.
An interpretation from a certified geneticist would also be included.
Genomic tests can help predict:
This is important because the cells of a tumor can mutate rapidly.
If a tumor suddenly mutates, a genomic test can spot if the mutation is receptive to targeted therapy.
One example is the drug Nerlynx (neratinib) used to target and treat early-stageHER2-positive breast cancer.
2017;24(5):229-38.
Kohler, J.; Turbitt, E.; and Biesecker, B.
