The Effects of Specific Latent Fingerprint and Questioned Document Examinations on the Amplification and Typing of the HLA DQ alpha Gene Region in Forensic Casework

Abstract

The apparent stability of DNA in forensic samples has permitted the successful application of several techniques such as polymerase chain reaction (PCR)-based and restriction fragment length polymorphisms (RFLP) analysis to forensic cases. PCR-based typing of the HLA-DQ alpha region in forensic casework has been shown to be a valid and reliable technique. This inherent stability of DNA in forensic evidence has led us to address the question of whether DNA could successfully withstand certain evidence processes such as latent fingerprint and electrostatic detection apparatus (ESDA) processing and still yield a sufficient quantity and quality of DNA for PCR HLA DQ alpha typing. Through testing done with biological material on simulated and casework envelope, stamp, and cigarette butt type evidence, it was determined that samples could be processed for specific latent fingerprint and ESDA examinations and still yield sufficient DNA for conclusive HLA DQ alpha typing results.

DNA Analysis and Document Examination: The Impact of Each Technique on Respective Analyses

“…Some of the more significant studies into recovering DNA from documents have utilized a digestion method, whereby part of the document is excised and digested to recover the DNA . This destruction could potentially limit or preclude any further analysis by subsequent examiners.…”

Recovery of DNA Profiles from Fingerprints on Paper after the Application of Ninhydrin or DFO Given Certain Time Periods

“…HLA DQ-α requires a reverse dot bot system and a colorimetric detection system where the probes were placed onto a nylon membrane and a biotin labeled product was hybridized with the probes [7]. HLA DQ-α typing was examined on simulated and casework envelopes, stamps and cigarette butt type evidence and questioned documents; it was determined that sufficient DNA was possible for HLA DQ-α, even after latent print and ESDA examinations [8]. DNA analysis has evolved to the present procedures today through two important developments: polymerase chain reaction (PCR) and short tandem repeat (STR) analysis.…”