Effects of Presumptive Test Reagents on the Ability to Obtain Restriction Fragment Length Polymorphism (RFLP) Patterns from Human Blood and Semen Stains
Hochmeister, MN
Forensic scientist, Department of Forensic Medicine, Bern, Switzerland.

Budowle, B
Research chemists, Forensic Science Research and Training Center, Laboratory Division, FBI Academy, Quantico, VA.

Baechtel, FS
Research chemists, Forensic Science Research and Training Center, Laboratory Division, FBI Academy, Quantico, VA.


Abstract
Some of the commonly used presumptive test reagents for identification of blood and semen could potentially affect the recovery of intact high-molecular-weight deoxyribonucleic acid (DNA) from evidentiary samples. Thus, the capability of performing restriction fragment length polymorphism (RFLP) analysis on evidentiary samples could be compromised.
In order to investigate the potential effects of presumptive test reagents on the DNA present in these samples, bloodstains on cotton and glass were exposed directly to luminol, benzidine, phenolphthalein, o-tolidine, and leucomalachite green, while semen stains and vaginal swabs containing semen were exposed directly to bromochloroindolyl phosphate (BCIP) and sodium thymolphthalein monophosphate (STMP) reagents.
The yield gels for DNA quality and quantity and RFLP results indicated that bloodstains exposed to luminol, benzidine dissolved in ethanol, and phenolphthalein, as well as semen stains and vaginal swabs exposed to BCIP and STMP yield RFLP patterns consistent with that of the uncontaminated control. Except for the phenolphthalein treatment, the quantity of extractable, high-molecular-weight DNA obtained was comparable with that of untreated stains. Therefore, evidentiary material purposely or inadvertently contaminated with these reagents can be successfully typed. However, stains exposed to benzidine dissolved in glacial acetic acid, leucomalachite green, and o-tolidine failed to yield high-molecular-weight DNA or to produce any RFLP patterns.

Keywords:
body fluids, criminalistics, deoxyribonucleic acid (DNA), forensic science, identification of blood, identification of semen, presumptive tests, RFLP

Paper ID: JFS363910656

ASTM International is a member of CrossRef.
Author Hochmeister MN, Budowle B, Baechtel FS Title Effects of Presumptive Test Reagents on the Ability to Obtain Restriction Fragment Length Polymorphism (RFLP) Patterns from Human Blood and Semen Stains Symposium , Committee on