The U.S. Food and Drug Administration (FDA) has issued a final rule that will regulate many laboratory-developed tests (LDTs) as medical devices. This new regulation targets approximately 12,000 laboratories, requiring them to submit their tests for FDA approval. The rule aims to enhance oversight over LDTs, which include tests for cancer, prenatal screenings, and rare diseases, that previously operated without significant federal oversight. The decision follows years of debate and is partly based on findings from ProPublica's investigations into prenatal genetic screenings and coronavirus tests.