We established an extremely simple method for visually detecting LAMP products in a sequence-specific manner by simply adding a small amount of low-molecularweight PEI to the LAMP reaction solution. The biggest feature of this technique is the ability to visually present sequence information of amplicons without using an expensive source of light or a detector. In contrast, conventional genetic tests require expensive reagents, complex and skillful manipulation, and large devices equipped with an expensive optical system. These are the main reasons why genetic testing is kept within the walls of specific institutions or university laboratories with special equipment and trained engineers. The combination of the LAMP method and the new detection method described here can overcome several factors that have been preventing true practical application of super-simple g-POCT devices for genetic testing. If a simple, inexpensive g-POCT device that is small and light enough to be held in one hand and whose main components are disposable can be developed, the day when parents will be able to genetically test for a pathogen while sitting next to the bed of their child who has a fever will not be far off [16] .