Blame it on Southern, but it's a western blot.

Edwin M. Southern is a professor emeritus at the University of Oxford. He is perhaps best known for development of the "Southern blot" (Dr. Southern was at the University of Edinburgh when he wrote his landmark paper). The Southern blot provided a scientific breakthrough by allowing scientists to detect a particular DNA sequence without first purifying it from the rest of the genome; the basic method involves the transfer of the DNA to a membrane, followed by detection with a specific probe. Although few people perform Southern blots as originally carried out by Southern, due in part to the more recent technique of the polymerase chain reaction, the basic concept continues to play an important role in molecular biology.