Almost 1 in 8 persons who underwent predictive genomic testing discovered they had a genetic risk for a health issue and may be able to manage it better with preventive care, according to a recent study published in Mayo Clinic Proceedings. It is anticipated that rising adoption of healthier lifestyles and growing genomics knowledge would increase demand for predictive genomic testing.
Genome sequencing prices have dropped over the past ten years from roughly $100 per gigabase to $10 per gigabase, and they are expected to drop much more in the near future to about $5 per gigabase. The adoption of genomic tests for cancer risk assessment, reproductive health decision-making, diagnosis of pre-existing monogenic conditions, prediction and monitoring of treatment response in cancer, and most recently for the surveillance of infectious diseases, including COVID-19, has significantly increased in tandem with this dramatic reduction. In addition, national population genomic programmes like Genomics England have encouraged the adoption of genomics throughout the whole healthcare ecosystem in these nations. In the US, compared to 2015, when few players even had policies, more than half of insured people (private or public) have insurance coverage for genetic testing now. In the US, there are over 10,000 sequencing-based genetic diagnostic products available. Even in India, the number of clinical genetic tests has increased from very little in 2015 to somewhere over 100,000 presently.
The growing use of genetic tests for preventive wellness has been spurred in recent years by a combination of rapid knowledge expansion and significant cost reduction. Almost 1 in 8 persons who underwent predictive genomic testing discovered they had a genetic risk for a health issue and may be able to manage it better with preventive care, according to a recent study published in Mayo Clinic Proceedings. It is anticipated that rising adoption of healthier lifestyles and growing genomics knowledge would increase demand for predictive genomic testing.
When well-known Hollywood celebrity Angelina Jolie went on to explain how her doctors determined she had an 87 percent risk of breast cancer and a 50 percent risk of ovarian cancer due to a genetic variation in the BRCA1 gene about ten years ago, genomic testing received the attention it deserved. Contrast this with the lifetime risk of breast/ovarian cancer for the typical woman, which is less than 15%. Jolie had preventive surgery, which decreased her risk to that of the typical woman her age.
Why is universal screening important?
Medical recommendations have long held that it is more cost-effective to limit preventive genetic testing for breast and ovarian cancer to individuals who are most at risk, such as the relatives of cancer patients who are now healthy. Evidence suggests that this strategy misses more than half of the people at risk, and a call for universal screening is growing stronger.
The fact that test costs have dropped to around $150 from as much as a few thousand dollars a decade ago is helping the move toward universal screening. If all women in India underwent preventative screening, according to health economic research, 250,000 lives may be saved; the overall cost of doing so would equate to an additional expenditure of $5,000 for every additional year of improved quality of life.
Beyond Cancer, Preventive Genomic Testing
Preventive genetic testing is not just useful for disorders like cancer. Studies on sudden unexplained deaths in seemingly healthy people have revealed that 13% of these people have genomic variations that cause channelopathies, a class of cardiac diseases that make the heart susceptible to abnormal rhythms even though it retains structural integrity and its coronary arteries are unobstructed. According to a fairly recent study, genetic variations that induce cardiomyopathies—abnormal structural changes to the heart—cause 15% of these deaths. However, these structural alterations are hidden or not visible at the time of death, with arrhythmia developing even before these abnormalities are visible. It goes without saying that in these circumstances, early discovery and risk management are vital, as is reassuring affected individuals’ families that they do not contain the genetic mutation that increases their risk.
Genomic testing to identify risks to one’s children as a preventative measure
Genomic testing for disease prevention can be used to determine hazards for one’s offspring as well as one’s own disease risk. One of the 5000 so-called monogenic disorders is caused by a genetic mutation that is carried by more than 50% of the population. For instance, 1 in 25 people in India are carriers of beta thalassemia, a condition that necessitates recurrent blood transfusions throughout one’s life. The majority of our genes are carried twice in each of us, once by our mother and once by our father. When a problematic genomic mutation is present in BOTH the maternal copy and the paternal copy, the majority of these monogenic illnesses manifest. It’s possible that both parents are only silent carriers of one genetic variation each. Preventive genetic testing is the only way to identify a carrier for the majority of the 5000 diseases. Numerous technological tools are now accessible to aid in a safe delivery when a couple learns they are both carriers for a specific gene.
Developing Cases
There are numerous such examples, such as those in which risk management for persons in danger is still a subject of ongoing study. Australian actor Chris Hemsworth was recently notified that he had two copies of a genetic variation in the APOE gene, which increased his risk of Alzheimer’s disease by 8–10 times. Because of a genetic variation in the LRRK2 gene, Sergei Brin, a co-founder of Google, has a significant statistical likelihood (more than 50%) of developing Parkinson’s disease, a degenerative condition of the central nervous system.
What Can/Cannot Genomics Do?
Specifically for aging-related diseases, there is a nuance to be aware of regarding preventive genomics: our individual disease risk is influenced by our lifestyle, our environment, and countless genetic variants in our genome. These elements interact in a complicated way. Preventive genomic screening can help identify and manage some key risks in situations where a small number of genomic variants contribute significantly to the overall risk and where lifestyle or therapeutic interventions can delay disease onset or reduce risk, as in some of the examples above, even though preventive genomic screening cannot completely eliminate disease risk caused by these complex interactions.
