(Selected Tables and Figures referenced, but not present in this blog
can be found in their corresponding Science Version blogs)
The use of the word “cure” in medicine always needs delicate consideration. If you recall, the only times I have used the word in earlier blogs was where I was describing the value of “removing the cause” in immune-inflammatory disease. The only place I would consider medical care’s potential to achieve a “cure” in health care, especially for autoimmune diseases and cancers lies in the current and evolving genetic therapies we will now discuss. They include CAR-T and CAAR-T cell replacement therapies, and CRISPR-Cas9 gene editing. Sometimes referred to as “genetic engineering” or “genetic modification,” these procedures can be defined as the direct manipulation of the genome using molecular biology engineering techniques. These engineering techniques for modifying genes can be applied in two very different ways: somatic genetic modification or modifications of selective genes of the body; and germline genetic modification or modifications of the entire genome.
Somatic genetic modification add, cut, or change the genes in some of the cells of an existing person, typically to alleviate a medical condition. A number of these gene therapy techniques are now FDA-approved for specific conditions. Germline genetic modification, quite different from “gene editing,” is used to “change” the genes in eggs, sperm, or early embryos. A number of these therapies are also FDA-approved, but, as of this writing, they are under intense scrutiny because of serious issues in that genetic engineering stands the risk of going well beyond the science and safety of the field. Bioethical questions also abound regarding potential uses and misuses of this germline bioscience as well as AI applications expanding its potential beyond therapeutic purposes. To wit, some controversial uses of genetic engineering include (but are not limited to):
Human genetic enhancement: The intentional modification of the human genome to “improve” individuals;
Human germline genome editing: Introducing heritable changes to sperm, eggs, or embryos;
Eugenics: (Eugenics is from a Greek word meaning “normal genes.”) Its modern definition describes it as the attempt to direct human heredity and evolution to ensure procreative advantage to more “desirable” human beings and to discourage or limit reproduction by the less desirable (that sounds like a pretty ugly proposition to me);
Genetic cloning: Cloning describes the processes used to create an exact genetic replica of another cell, tissue, or organism. The copied material that has the same genetic makeup as the original is referred to as a clone. Of course, the use of genetic cloning for monoclonal antibodies as discussed in Blog #21 is an enormously valuable procedure.
The ethics and pros and cons of all of these techniques are under excruciating analysis and review by international bioethics groups. Undoubtedly laws and regulations will be instituted in the coming years to mitigate the dangers of these technologies while maximizing their value in healthcare. As such, in the next few blogs we’ll look at each of the procedures and their therapeutic applications and implications.
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