Genetics is an immensely complex and yet critically important field of study in medicine and health science. Every year, advancements in technology allow for the development of new tests, new ways of understanding how genes map to illnesses, and the gene networks and gene expression that make up everything about how a living creature is the way it is.
Genetics isn't simple. A huge array of illnesses have genetic components, but genes also control everything from the fur coat patterns on a cat or dog to the development of organs and much more. However, it's not as easy as saying, "This animal has the gene for cancer"; there are many genes that are related to different aspects of different illnesses in different ways, and these relationships are poorly understood.
A huge part of the current advancements in genetics and genomics in veterinary medicine centers around building this body of knowledge. Through the study of numerous animals, and through the correlations between them and their diseases, relationships can be built between genes and illnesses. This can help with veterinary medicine in several ways.
Note: We'll largely refer to genetics and genomics as the same overall field throughout this post. There's a difference between the two, but they're closely related. Genetics is the study of individual genes and how they express; genomics is the study of the genome, the whole cluster of genes, and the maps and relations between them. They're two facets of the same field, and both provide similar kinds of benefits for veterinary medicine.
How, precisely, can genetics and genomics benefit veterinary medicine, now and in the future? Let's consider the benefits.
Classifying the Benefits of Modern Genetics and Genomics
In broad strokes, the modern study of genetics and genomics brings benefits in a few distinct ways. We'll break down each of those ways later, but it's worth talking about the overarching framework.
The first is "genetics as prognostics." Prognostication, or prediction, is a way to perform a genetic screening before anything has gone wrong. Indeed, it can be performed on young animals at their first checkup and is as minimally invasive as a cheek swab. These tests can be sequenced and examined, searching for the risk factors that may be present in a given patient.
From there, you can establish a life-long protocol of vigilance and testing, such as urinalysis or regular blood testing, to detect symptoms of a disease before it's even expressed itself enough to cause issues with the patient. In this way, certain diseases – and the list grows as more awareness of genomics is built up – can be caught and addressed long before they would normally have even been discovered.
The second sphere is "genetics as diagnostics." Diagnostics involves testing to identify the actual root cause of a disease. Cancer is the biggest example, of course, being able to use genetic sequencing to identify what kind of cancer and what specific sub-variant of cancer may be in play.
A note about how cancer works. Cancer is, generally, the uncontrolled replication of cells in a disorderly fashion. It's caused by a mutation in a cell that prevents it from being limited like other cells and also evades detection by the body's immune system.
Imagine it like this. Genes are a series of switches. Cancer is what happens when a certain selection of those switches is switched to the wrong positions. If only a few of them are switched wrong, the cancer doesn't spread; if all of them are flipped, the cancer grows.
While any creature can, over time, develop enough mutations to eventually flip all of those switches, some animals are born with certain risk factors. Those risk factors are, essentially, some of those switches being pre-flipped.
Diagnostic tests can identify what set of mutations may be present and can consequently identify cancer strains and what treatments are likely to work.
The third sphere is "genetics as treatment." Using genetics, unique features of a disease like cancer can be identified, and then that information can be used to develop treatments.
Modern cancer treatments often work by exploiting the fact that cancer is ravenous and divides more rapidly than other cells; by delivering systemic poison, the cancer sucks it up faster than normal cells and dies while the normal cells survive. This can be both risky and ineffective. However, by identifying specifics of cancer cells and developing treatments that target those specific mutations, treatments can target cancer exclusively and leave normal cells alone, making for "silver bullet" treatments.
For the most part, all of these forefronts of medicine are being pushed in human oncology ahead of veterinary medicine. However, when methodologies are identified, similar methodologies can be applied in veterinary medicine.
Let's look at more specific examples of these spheres.
Genetics Can More Accurately Diagnose Illnesses
Over time, the study of genomics and genetics has identified patterns and correlations between certain gene expressions and certain illnesses. Cancer is one of the biggest examples. "Cancer" is a class of disease; there are many different kinds of cancer, and no two cancers are the same. However, certain types of cancer are correlated with the presence or lack of certain genes in certain expressions.
By studying and understanding the correlations, veterinary scientists have been working on developing tests that can check a biopsy sample and determine if the sample is cancer, and if so, what kind of cancer. One current example is the OnxoK9 multi-cancer detection test, developed in partnership between Antech and PetDx. This genomic sequencing test can be used on a sample and can determine whether or not it's one of 30 different types of common canine cancers.
This allows for fast triage and a rapid understanding of what a cancer is so treatment can be developed immediately. This can speed up diagnosis, lower the time to treatment, and even improve the efficacy of treatment by knowing which specific cancer is in play rather than a broad spectrum of disease.
Genetics Can Predict At-Risk Illnesses
Predictive screening is also a powerful tool aided by an increasing understanding of pet genetics and genomics. Frequently, with as little as a simple sample of blood or tissue, a screening test can be performed that can look for and identify the presence or expression of certain genes that correlate to specific illnesses.
This kind of predictive panel can be used as proactive medicine. By testing an animal, canine, feline, or other, certain risk factors can be identified. This allows the pet owner and vet to work together to watch for specific symptoms or behaviors that might indicate the development of that disease and to proactively manage or treat it if it appears.
Genetics is not a simple one-to-one, however. The presence of risk factor genes does not guarantee the pet will develop a given illness; it is simply correlated with an increased incidence of that illness. In fact, one of the biggest challenges with genetics and genomics, in both human and veterinary medicine, is that there's nothing so easily clear-cut yet discovered. There are correlations but no guarantees.
Genetics Can Predict More Effective Treatments
Another example of how genetics and genomics can aid in veterinary medicine is the correlations between specific genes present in something like cancer and their correlation to efficacy in treatment.
For example, there's a gene known as MDR1. This gene is sporadically present in certain kinds of cancers and correlates to an increased sensitivity to certain chemotherapy drugs. So, when a dog is diagnosed with one of those cancers, a test can check for that gene, and if it's present, the vet knows that the cancer is more likely to be receptive to treatment with those specific chemotherapy drugs. Conversely, if the gene is absent, it indicates the drugs may not be as effective.
All of this allows for more predictive and customized treatments. Instead of starting a dog on a chemotherapy regimen and hoping it works, a vet can have a better idea of whether or not it's likely to work and can pursue a treatment most likely to be effective for a given patient.
This isn't theoretical; Vidium has produced a test called Searchlight DNA, which can identify mutations in cancer genes, identify chemosensitivity via checking for MDR1, scans for over 120 other relevant cancer genes, and provide a detailed report of recommended treatment options for that specific patient.
Genetics for Informed Breeding
Moving away from pet-focused veterinary care into other forms of animal health, breeding is a significant component of, for example, cattle and other livestock. Keeping breed lines healthy, breeding away risk factors for illness, and selecting favorable traits are all aspects of genetics that have been in practice since millennia before anyone knew what a "gene" even was.
With deeper and more detailed studies into animal genetics and genomics, more advanced awareness of those genes and lineage factors can be leveraged to improve the overall outcomes of breeding programs. This can be used in a wide variety of ways, from breeding more disease-resistant animals to attempting to eliminate the mutations that make an animal more susceptible to certain diseases.
This is, truth be told, one of the original uses of genetics in animal medicine. For many vets, particularly those who don't work much with livestock and who aren't concerned with breeding pets (when those pets are spayed or neutered), it's not something they're keen to watch. However, the same technology and methodology can apply to breeding companion animals, both for purebred purposes and simply as a way to help local breeders produce healthy animals.
Advancements in Machine Learning for Analysis
Computational genomics is growing in power every year, with more investment and better technology. Machine learning and some subsets of AIs are being used to comb through the records of millions of DNA tests over decades. This can identify patterns and correlations on a broader scale than any one vet could, and Big Tech investment is glowing at the opportunity.
A word of caution: The modern use of AI is a combination of buzzwords, scams, and marketing as much as it is real technology. The common use of AI is for generative AI, which isn't studying information and learning from it so much as identifying its patterns and learning to replicate them. Something like a GPT isn't valuable in this space. However, more advanced forms of machine learning and analytics powered by neural networks are much more effective – and faster – than manually identifying patterns and correlations, and that's what a good portion of veterinary AI is doing.
Before investing in a veterinary AI startup, make sure they can adequately explain what their AI is and does; if it's just a buzzword for statistical analysis, it's perhaps less valuable than more advanced uses of the technology.
Controversy in Genetics: the Ethics of Gene Modification
Along with any novel discoveries in medicine come ethical questions. With genes, in particular, a question arises: is it ethical to edit a genomic sequence before an animal is even born?
Few would argue that it's unethical to reduce the chances of life-ending disease by editing an embryo. However, gene modification is a contentious subject, such that "genetically-modified organism" is a stigma attached to foods, and it's an ethical line in the sand for some pet owners and activists.
This is a field of ethical and philosophical discussion that is quickly becoming a reality. Some argue that it's unethical to not work to minimize the chances of disease; others argue that it's a short hop to gene editing for cosmetic purposes, which opens up a door that can never again be closed.
There's no answer to this question, not yet. It's something that any vet looking into genetic therapies and testing will need to be aware of in the coming years.
Making Use of Modern Genetics Technology
One of the greatest challenges for any vet is keeping up with advancements in veterinary technology, and that includes genetics and genomics. While you don't need to be a geneticist to make use of the technology, it can certainly feel like it's almost unbelievable to the layman, and as a vet, you have a responsibility to understand it at least enough to explain it to your clients.
Fortunately, as the technology develops, so too will awareness. We're right here with you. As experts in a variety of veterinary topics, from oncology to dermatology to neurology, we try to help both patients and veterinarians who need assistance. If you need a consultation, we're more than happy to help.
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