New Era of Health Care
Author: Ridhi Bhat
Although the term precision medicine is relatively recent, this idea has played a big role in the field of health care for many years. For instance, the person who needs blood transfusion receives blood from a matched donor to reduce the risks of complications. At present, the field of precision medicine is still in its early stage. Researchers hope that this field will extend to various aspects of health care in the coming years. Here, we are going to discuss the topic of precision medicine and its impact on our lives.
Sequencing of the genome may be an effective tool to enhance patient care by improving diagnostic sensitivity and precisely targeting therapeutic intervention. The need to change the medical system for the better and provide more precise diagnoses is very well understood in today’s world. As a result of precision medicine, each patient will receive individualized treatment tailored to meet their unique genetic, biomarker, phenotypic, psychological, and social needs. Various ‘new generation’ technologies and a steep incline in sequencing the genome has led to facilitate more affordable and large-scale research. This field gained more spotlight after the initiative taken by Ex-President Obama, who, set aside a hefty budget of $215 million in the session of 2016 for research work in this field. It was understood that, traditionally, most medical treatments cater for the "average patient." These methods involve "one-size-fits-all" treatments, which can be extremely effective for some people, but not for others. The latest research suggests that this technology can be used to effectively cure various genetic diseases like Huntington’s disease, Parkinson’s disease, Alzheimer’s disease, Cystic Fibrosis, etc. Various advancements are being made by using precision medicine in treating various types of cancers. Despite being a beacon of hope for the new emerging technologies and medical advancement, it has its downsides. We shall now discuss certain aspects of precision medicine in brief.
The merge of genome discovery and clinical genetics:
In 1976, human genetics was revolutionized by cloning human genes for the very first time. By the year 1986, transgenic methods, knock-out and knock-in were introduced, and in about 1996, database searches became a vital tool for genomic research. Molecular genomics consists of two phases, structural and functional. Structural genomics involves the assemblage of genetic, physical, and transcriptase maps of an organism, which is the first phase of genomic analysis. They generally try to understand the observational characteristics that make genotypic variation to phenotypic variation using genetic and physical mapping. Developing systematic methods for finding genes of interest and their functions, resulting from the collection of partially sequenced complementary DNA clones, is part of functional genomics. The accumulation of human gene sequences provides the capability for developing systematic methods for discovering genes of interest.
While diagnostic testing has been historically focused on karyotyping to find chromosomal abnormalities in clinical medicine and situ hybridization for detecting large-scale rearrangements. The link between clinical genetics with diseases led to the discovery of Sanger’s method. As a method of DNA sequencing, Sanger sequencing makes use of the selective incorporation of chain-terminating di-deoxynucleotides by DNA polymerase during in vitro replication. With more discoveries under its belt, the new method is expected to not only provide better efficiency, but also the best safety profile.
Clinically speaking, at the surface, all the symptoms of a disease appear to be uniform. But, on the genomic level, the polygenic network of medicine will react and influence the phenotypic trait. This may also prove to be an elixir to some and poison to the rest.
Genetic therapy is the process of modifying cells so they can produce a therapeutic effect or treat diseases by repairing or re-constructing their genetic material. Gene therapy works in different ways to provide therapeutic effects. They are stated as follows:
- Gene replacement for a disease-causing gene
- Genes that cause diseases by failing to function are inactivated
- An experimental approach to treating diseases by providing a new or modified gene
Researchers are studying gene therapy products to treat diseases such as cancer, genetic diseases, and infectious diseases.
Gene therapy consists of numerous types of methods, including:
- Genes can be inserted into human cells by genetically engineering circular DNA molecules.
- In some gene therapy products, genetic material is delivered into cells by viruses. Viruses can deliver genetic material into cells naturally. Once these modified viruses (vehicles) have been modified and weakened to remove their infectious ability, they could be used to deliver therapeutic genes to human cells.
- It may be possible to modify bacteria so that they cannot cause infectious disease and then to use them as vectors (vehicles) to deliver therapeutic genes to the human body.
- Aims of gene editing on humans: Disrupting harmful genes and repairing mutated genes are the goals of gene editing.
- Patient-derived cellular gene therapy products: The patient's cells are removed and genetically modified (by using a viral vector). The cells are then returned to the patient.
As drug development progresses, genomics will be increasingly important, especially to provide a deeper understanding of disease molecular mechanisms and drug responses. The development of modern genetics will significantly alter the way health care is delivered. Various government-funded projects on precision medicine are being executed at present. Currently, this field is said to be in its initial stage. Researchers are expecting that this field will only grow as a promise for a better future. The precision in diagnostics, preventive measures, and overall population health make it a golden opportunity.
Speaking in contrast to the argument presented, any error in the clinical tests for the genome can lead to serious consequences. This can lead to genetic diseases for the individual and his or her family. Apart from this obvious issue, infrastructural requirements and healthcare costs will also bespeak an exorbitant amount of capital. A legal issue regarding the collected genomic data of a large population also becomes a major hurdle in the advancement of this field. A global discussion, cooperation, and resolutions will be required on genomic research and its clinical application effects, not only on technical issues such as patent protection but also on more complex issues such as welfare and morality.
✢ Larry Jameson, J.; Longo, Dan L. Precision Medicine—Personalized, Problematic, and Promising, Obstetrical & Gynecological Survey: October 2015 - Volume 70 - Issue 10 - p 612-614. Retrieved from: https://doi:10.1097/01.ogx.0000472121.21647.38
✢ Koenig, I. R., Fuchs, O., Hansen, G., von Mutius, E., & Kopp, M. V. (2017). What is precision medicine?. European respiratory journal, 50(4). Retrieved from: doi:10.1183/13993003.00391-2017
✢ Ashley, E. A. (2016). Towards precision medicine. Nature Reviews Genetics, 17(9), 507-522. Retrieved from: https://doi.org/10.1038/nrg.2016.86
✢ Hodson, R. (2016). Precision medicine. Nature, 537(7619), S49-S49. Retrieved from: https://doi.org/10.1038/537S49a
✢ Kosorok, M. R., & Laber, E. B. (2019). Precision medicine. Annual review of statistics and its application, 6, 263-286. Retrieved from: https://doi.org/10.1146/annurev-statistics-030718-105251
✢ Bahcall, O. (2015). Precision medicine. Nature, 526(7573), 335. Retrieved from: https://doi.org/10.1038/526335a
✢ (2018, July 25). What is Gene Therapy? FDA. Retrieved July 7, 2021, from https://www.fda.gov/vaccines-blood-biologics/cellular-gene-therapy-products/what-gene-therapy
✢ O. O. P. S. (2015, January 30). FACT SHEET: President Obama's Precision Medicine Initiative. The White House. Retrieved July 5, 2021, from https://obamawhitehouse.archives.gov/the-press-office/2015/01/30/fact-sheet-president-obama-s-precision-medicine-initiative
About the Author:
Ridhi Bhat, a graduate student of the University School of Chemical Technology, GGSIP University, Delhi. She is pursuing her degree in Biochemical engineering.