How the Dogs Assist with Research
The dogs of PADs are assisting with research into Parkinson’s Disease in two important ways:
The dogs are helping to locate and isolate the molecules in the odor of Parkinson’s Disease. Dogs are highly selective, even more so than laboratory equipment, in their ability to sort volatile organic compounds from a complex background of odorant molecules. When sniffing, dogs can sort and be trained to select compounds in parts per million. By isolating and identifying the odor that the dogs are identifying in Parkinson’s Disease, important progress can be made in the search for a biomarker of Parkinson’s. A biomarker is important because it helps to point the way to a cause of the disease. And understanding the cause becomes an important step on the path towards finding the cure.
At PADs, the dogs are presented with different organic compounds that may or may not be present in Parkinson’s Disease. The dogs provide feedback on whether the laboratory-produced compound is representative of what they are smelling in actual samples from Parkinson’s participants. When a compound is selected as “hot” by the dogs (think of this as watching a suspect being picked from a line up on Law and Order) then this compound is studied further in the lab, and mass spectrometry equipment is used to examine Parkinson’s participant samples to determine if this same compound can be found in Parkinson’s Disease. (Think of this step as dusting the suspect for finger prints and then taking a DNA sample once the suspect is identified in the line-up.) This is how chemistry and canine detection are working together to solve the mystery of Parkinson’s.
The dogs are also helping with clinical trial work on Parkinson’s therapeutic treatment plans. Since Parkinson's can mimic other diseases, there can be a rate of anywhere from 10-25% misdiagnosis in Parkinson’s. Consequently, it is possible that not all patients who participate in a clinical trial have Parkinson’s Disease. It is also theorized that the odor associated with Parkinson’s may change, or diminish, if a treatment is successful. The dogs of PADs are providing feedback on samples provided from participants in a clinical trial as a data point in the trial results. Kit samples are sent to the dogs (completely blind on participant information) and the dogs are then presented with blind samples and they provide information on whether a sample is hot (has the associated odor they are trained on) or cold (no associated odor present.)
For research purposes, it is important for PADs to maintain a high number of dogs in the Program, so that testing results can be duplicated between groups of dogs.