DNA recovery from immunochromatographic membranes

The detection and confirmation of human body fluids as being human is crucial in crime scene investigations. Human body fluids, especially blood, saliva and semen, are often recovered from a variety of crime scenes, sometimes in extremely low quantities. The reliable identification of human body fluids could be of critical value to investigators and contributes toward solving crimes. Traditional serological techniques, used as confirmatory test, can be time-consuming and often may require large amounts of biological sample. Due to these features, often this laboratory phase is omitted carrying out directly DNA isolation in order to identify the genetic profile characterizing analyzed traces. Our work demonstrates, using three commercially available membranes, representing by HemDirect Hemoglobin Assay (Seratec), -Amylase Test (Seratec) and PSA semiquant test (Seratec), the possibility to recover human DNA swabbing the inner surfaces of the membranes used. This protocol is able to recover DNA useful for genetic identification; this fraction alone or together with remaining fraction not used for the immunoassay test, allows to carry out the confirmation tests, reducing the destructiveness of the reaction itself.