 More recently, companies such as Parabon NanoLabs and Identitas have begun offering forensic DNA phenotyping services for U.S. and international law enforcement.DNA phenotyping is often referred to as a "biologic witness," a play on the term eye-witness.Just as an eye-witness may describe the appearance of a person of interest, the DNA left at a crime scene can be used to discover the physical appearance of the person who left it.