Southern Blot Open Access Journals The strategy in atomic science to distinguish explicit DNA arrangement in DNA tests is known as southern smudge. Southern smear is otherwise called DNA blotch. The name southern smear is named on the name of researcher Southern.A Southern smudge is a strategy utilized in atomic science for recognition of a particular DNA arrangement in DNA tests. Southern blotching consolidates move of electrophoresis - isolated DNA sections to a channel film and resulting part identification by test hybridization.Southern smudge autoradiogram. A Southern smudge is a technique utilized in sub-atomic science for recognition of a particular DNA arrangement in DNA tests. Southern smudging consolidates move of electrophoresis - isolated DNA pieces to a channel layer and ensuing part discovery by test hybridization.