Chytridiomycosis is a highly infectious disease that affected at least 501 amphibian populations and is found on all continents except Antarctica. Chytrid fungi cause pathological dermal effects disrupting vital functions of amphibian skin, such as regulation of respiration and temperature, osmotic balance, reproduction, and electrolyte transport. Hence, the skin attacking fungus is often lethal to certain amphibian species and leads to substantial losses in biodiversity. Despite the plethora of studies addressing the host-pathogen interactions, the origin and the infection dynamics of the Chytridiomycosis are far from being understood. Thus, it is almost impossible to monitor and combat disease outbreaks. And due to the absence of an amphibian population control strategy, the species continue to be under the threat of extinction.
Although the monitoring of the disease spread is difficult to achieve, it’s possible to conserve the extent of the amphibian population affected through the establishment of disease-free colonies using a point of care diagnostic device. The NYUAD iGEM team has been developing Chytritect, an automated diagnostic device capable of extracting the DNA and detecting the presence of the pathogen in under 30 minutes. To get the result, a user needs to swab the amphibian skin and place the swab in the device which contains a tube with a lysis buffer. The lysed sample will be then transported to a microfluidic chip that extracts the DNA with surface chemistry and connects to a concentrator with CRISPR-Cas12a components to detect the presence of the disease. A fluorescence signal indicates to the device that the amphibian has tested positive.
The existing methods of pathogen detection are time-consuming and labor-intensive which delay and complicate the disease control strategies. To run conventional PCR you would need specialized equipment, expensive reagents, and well-trained lab assistants, all of which are unavailable in the field. Our microfluidic chip-based device integrating PCR beings an easy and quick point of care testing. Chytritect is advantageous to current tube-based PCR in terms of lower component consumption, lower detection time frame, lower cost per test, and simple use method which can be undertaken by minimally trained personnel. The device is portable, capable of detecting two fungus genes simultaneously, and uses disposable chips eliminating the odds of sample contamination. Therefore, the device design is well suited for rapid detection of the two disease-causing fungal species in a field setting.
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