Genetic testing offers many benefits, including providing important information that can be used when making decisions about having a family and taking care of one’s own health. However, there are also risks and limitations to testing. For this reason, it is important to understand the nature of genetic testing and the information that it can and can’t provide.
More Genetic Topics: Disorders | Testing Techniques | Applications | Infectious Diseases
Things to consider
The Future of Genetic Testing
With the completion of the Human Genome Project, we have learned that “correct”, “usual” and “normal” no longer have meaning when it comes to a person’s genetic makeup. Genetic variations occur in great numbers in our genome. We are all unique, not only in our personalities and appearance, but in our genotypes as well. Scientists continue to work on ways to better understand the structure of our genetic makeup, which could allow for important advances in the prevention, detection and treatment of many disorders.
Gene therapy is an approach to treating potentially lethal and disabling disorders that are caused by single gene deficiencies. With specialized techniques, genes or gene expression can be manipulated in some disorders to remedy the problem in a particular patient. To do this, customized DNA is introduced into the affected cells or tissues so that the detrimental symptoms of the disorder are not expressed in the patient.
One specific gene-editing technique that has gained a lot of attention lately is CRISPR/Cas9. The technique uses the enzyme Cas9 to cut DNA at a targeted location. Once cut, the DNA is repaired by adding or removing pieces of genetic material or by replacing a segment of DNA with a customized sequence.
In most cases, gene therapy is still highly experimental. Clinical trials are being conducted to see if gene therapy can be used to develop treatments for other types of disorders, including cancer, heart disease, and HIV/AIDS. In 2017, the FDA approved gene therapy for leukemia, marking the first approval of gene therapy in the U.S.
Advances in technology and molecular biology laboratory techniques have opened up the fields of personalized medicine and pharmacogenomics. The ability to sequence an individual’s entire genome and to evaluate the RNA and proteins expressed by those genes is already leading to cancer treatments tailored to an individual’s and/or tumor’s genetics. As researchers continue to discover more biomarkers, genetic knowledge will allow for even greater customization of medical care. With that said, while technology has made great strides, current science does not have detailed knowledge of the function of every gene in the genome or the impact of every possible genetic change.
To assist in improving our knowledge, there are several movements with goals of collecting, curating and sharing genetic data. For example, ClinVar and ClinGen are two programs of the National Institutes of Health (NIH) that collect and share genomic data. ClinVar is a free and open-access database that collects information about genetic variations and their relationship to health. The goal of ClinGen is to build an authoritative resource on the medical relevance of genes and variants for scientists to use in their research. Individuals wishing to help improve personalized medicine can find out how to become involved at websites like ClinGen.
Further advances in genetic testing will eventually replace older methods of predicting prognosis, allow us to use targeted therapy only on those patients who will respond, and help guide further research into such therapies. Recent advances are also helping to increase our understanding of some complex disorders, including a variety of cancers. Without a doubt, there will be more and more advances in genetic research that will impact the laboratory tests available to all patients for detection and treatment of a variety of disorders.
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