Breast cancer is a disease in which cells in the breast grow uncontrollably, and it is the second most common cancer among women in Missouri and in the United States. One way to detect instances of breast cancer is to screen for microRNAs associated with breast cancer cell lines, which are present in the urine. We created a device similar to a pregnancy test designed to detect early-onset breast cancer using methods that are easier and less invasive than traditional methods. Our biosensor, called “myRNA,” contains a Cas13 protein that activates a quencher-fluorophore complex in the presence of miR-424-5p, a miRNA which is positively correlated with incidents of breast cancer.