the detecting sample chamber 224 and the comparison sample chamber 225 compressed gas can be introduced from the gas inlets 23 to facilitate the sample flowing between each connection path then as shown in fig3 the system for detecting mtdna alterations of the present embodiment comprises the aforementioned device 2 for detecting mtdna alterations a temperature controller 4 disposed surrounding the device 2 to control a temperature of the device 2 wherein the temperature controller 4 is disposed under the device 2 in the present embodiment and an analysis device 5 disposed over the device 2 to detect signals emitting from the sample contained in the device 2 herein the system for detecting mtdna alterations of the present embodiment further comprises a heater cooler device 3 which is disposed under the device 2 and connects to the temperature controller 4 in the present embodiment the heater cooler device 3 is a te cooler in addition the temperature controller 4 of the present embodiment comprises a temperature sensing module 41 a power supply 42 and a control module 43 the temperature sensing module 41 can detect the temperature of the device 2 the control module 43 can control the power supply 42 providing power to the heater cooler device 3 based on the temperature detected by the temperature sensing module 41 to increase or decrease.