Written by Pamil Tamelessio ‘25
Edited by Samuel Lew ‘24
Image source: Karolina Grabowska from Pexels
Dogs have co-evolved with humans for as long as 33,000 years, making them the species most integrated into human society [Thalmann]. The ancestors of our furry friends have worked alongside humans as hunters, protectors, and guides. They have also continuously adapted to our needs and wants, which have been instrumental in the survival of both humans and canines. Although our society has advanced past the need for hunting and gathering, dogs continue to adapt to changes in our society. Now, instead of sniffing out potential meals or staying alert for predators, dogs can be utilized for a different purpose: creating AIs.
Research shows that canines can recognize the state of our emotions by sensing chemically unique changes in the odor of our breath and sweat. This unique odor is induced by the sympathetic nervous system, which becomes activated during periods of stress and threatening situations. This causes the release of the neurotransmitter called norepinephrine to various organ sites, which sends adrenaline into the bloodstream. Increased exposure to stressful situations causes the sympathetic nervous system to continuously release adrenaline into the bloodstream, which eventually travels to our breath and sweat. The increase in adrenaline in our body odor is what our pets tend to recognize, which cues them in our current states of mind [Wilson].
This mechanism is also observed when canines can detect diseases such as cancer in their owners. The odor of prostate cancer in urine is caused by a set of specific volatile organic compounds (VOCs), which elicit unique odors that are distinguishable from other volatile organic compounds in urine. One VOC, called trimethyl silanol, causes the degradation of silicones and is commonly found in the urine of prostate cancer patients. Another way canines can identify prostate cancer in urine is through the absence of VOCs, such as 2-pentanone and pyrrole, which are typically found in the healthy control group samples. Unfortunately, due to a lack of consistent biomarkers, many machines are unable to accurately detect many of these volatile compounds in prostate cancer urine samples [Guest].
However, a study done on the practicality of dogs sensing the VOCs present in prostate cancer urine showed that dogs were able to accurately detect cancer approximately 75% of the time [Guest]. The research also suggests that canines were able to detect specific chemicals in prostate cancer urine samples that scientists and programs lack the biomarkers for. As a result, scientists are now utilizing canine diagnoses to train a type of AI called an Artificial Neural Network (ANN) to analyze the chemicals emanating from the urine of prostate cancer patients [Guest]. This artificial intelligence program is trained to weigh the results of the canine’s various diagnoses of prostate cancer urine samples until it achieves the results with the “highest weight”. In general, these AI programs can analyze the canine behaviors and patterns when diagnosing prostate cancer in urine, weigh its probability through a series of networks, and ultimately form a program that can detect cancer with high accuracy.
Dogs have been the reliable partners of humankind for thousands of years, adapting to our routines and societies to best accommodate our well-being. Although our society continues to advance and our pets may continue to evolve, we can always count on our furry friends to stay true to one purpose: being our trusted companions.
References
1. Guest C, Harris R, Sfanos KS, Shrestha E, Partin AW, Trock B, et al. Feasibility of integrating canine olfaction with chemical and microbial profiling of urine to detect lethal prostate cancer [Internet]. PLOS ONE. Public Library of Science; [cited 2022Nov21]. Available from: https://doi.org/10.1371/journal.pone.0245530
2. Wilson C, Campbell K, Petzel Z, Reeve C. Dogs can discriminate between human baseline and psychological stress condition odours [Internet]. PLOS ONE. Public Library of Science; [cited 2022Nov21]. Available from: https://doi.org/10.1371/journal.pone.0274143
3. Grabowska K. Shot of a man giving instruction on computer screen to a dog [Internet]. Pexels. 2020 [cited 2022Nov21]. Available from: https://www.pexels.com/photo/shot-of-a-man-giving-instruction-on-computer-screen-to-a-dog-5904050/
4. Thalmann O. Complete mitochondrial genomes of ancient canids ... - science | AAAS [Internet]. Science. Science; 2013 [cited 2022Nov21]. Available from: https://www.science.org/doi/10.1126/science.1243650