. A technician examines a tube containing a small pellet of DNA extracted from human white blood cells for use in DNA fingerprinting. Electrophoresis is used to separate selected DNA into a pattern of bands that is unique to one person. DNA fingerprinting can thus be used to prove family relationships, such as the paternity of a child, because some of the parent's DNA bands will match some of the bands in the child's fingerprint. The technique is also used to identify & convict criminals from blood, semen or hair left at the scene of a crime. Photo taken at ICI Cellmark Diagnostics, Oxfordshire. MODEL RELEASED