P.H. Whitehead

A Test Paper for Detecting Saliva Stains

A technique is described for the detection of saliva stains on cloth using a specially prepared amylase-sensitive test paper. The method simply involves pressing the suspect cloth or garment against moistened test paper and incubating for 15 minutes. The method of preparation of the test paper and its use is described.

Enzyme Typing of Human Hair Roots

Sufficient phosphoglucomutase activity was found to be present in plucked hair noses bearing either fragmentary or complete outer root sheaths to enable typing of individual roots by starch-gel electrophoresis. Hair roots collected by brushing were found to contain very little PGM activity. Other isoenzyme systems were detected in hair roots but in insufficient quantities to make typing feasible.

Polymorphic enzyme systems in human hair sheath cells.

Abstract Using starch gel electrophoresis, the enzymes Phospho-glucomutase (PGM 1 locus), Adenylate kinase, Esterase D, Glyoxalase, 6-Phosphogluconate dehydrogenase, Glucose-6-phosphate dehydrogenase and Phosphohexose isomerase could be detected in fresh hair sheath cells. Of these, all but Adenylate kinase could be detected in three-week-old sheath cells and of the remainder, all but Esterase D could be detected in seven-week-old sheath cells. Acid phosphatase and Adenosine deaminase enzyme activity was also detected but reliable typing was not possible. No Peptidase A activity could be detected.

An Improved Means of Enzyme Typing of Hair Roots Using Isoelectric Focusing

An improved method of grouping hair, based on the alleles of PGM observed by isoelectric focusing, has been described. The increased discriminating power of this system (0.77) compared to that obtained by the starch gel technique (0.55) provides a new and more sensitive means of typing hair.

The Identification of the Species Origin of Bloodstains Using Sensitized Latex

A batch of latex suspensions sensitized with immunoglobulins directed against the serum proteins of eleven different animals (including human) has been prepared. The results of testing these animal latex suspensions against homologous sera, heterologous sera and experimentally prepared bloodstains are described. In addition “non-specific” agglutination of the latex particles with human Rheumatoid Arthritis serum is described and discussed. Extracts prepared from stains of a variety of common household fluids did not agglutinate anti-human latex.

The distribution and significance of amylase-containing stains on clothing.

An amylase-sensitive test paper was used to screen seventy-two articles oj clothing for saliva stains. The clothes had not been washed since being worn. In every case amylase-positive material was found as a spatter of small stains on the upper front of the garment. Other parts of the garments, especially cuffs and pockets were frequently stained as well. The significance of these findings for the forensic serologist is discussed.

The Production and Evaluation of an Antiserum for the Detection of Human Saliva

An antiserum raised in rabbits against human whole saliva cross-reacted with human serum and semen. Affinity chromatography of the antiserum on columns of immobilised human serum and seminal protein absorbed out these cross-reacting antibodies leaving a major antibody which reacted with α-amylase in saliva and pancreatic juice. The absorbed antiserum was evaluated as a reagent for the specific detection of human saliva in stains of forensic interest ; in a blind trial consisting of 87 samples, 32 positives, 1 false negative and no false positives were obtained. The antiserum appears to be highly specific for human saliva and does not cross-react with that of eight species of popular domestic animals.

The Fractionation of ABH Blood Group Substances in Saliva

Samples of saliva from 16 secretors and 12 non-secretors have been fractionated by gel permeation chromatography on Sephadex G100 and the fractions tested for blood group activity using an auto-analyser. In contrast to previously reported work we detected only one blood group active component of high molecular weight in the eluate, and no further fractionation of saliva into lower molecular weight substances possessing blood group activity was found. Similar results were obtained when a range of anti-sera were studied. Attention is drawn to anomalous results that may be produced during GPC of protein-carbohydrate complexes as found in saliva due to adsorption or precipitation on the column.

The detection of Y chromosomes in bloodstains--a reevaluation.

A method has been described for detecting Y chromosomes in the leukocytes of human bloodstains prepared on a variety of substrates. The factors that influence the proportion of chromosomes exhibiting a Y spot (the Y cell index) in a bloodstain are considered, including the subjective nature of assessment of the Y chromosome fluorescence, the substrate, and the age of bloodstain. In contrast to previous workers no decay in Y cell index with the age of the stain was observed. The results of a blind trial involving stains derived from case work, where from other evidence there was no doubt as to the sex of the donor, are presented. Sixty-five percent of the male bloodstains were correctly identified and no females were wrongly reported as male.

The Detection of Allergen-Associated Antibodies in Bloodstains

A radio-immunoassay was used to detect the antibodies responsible for allergies (e.g., hay fever). It was found that these antibodies, which belong to the Ig E class of immunoglobulins, could be recovered from bloodstains. A small blind trial involving duplicate bloodstains from six individuals was conducted successfully. The stains were divided into a reference set and a coded set. Characterisation of the stains with four allergens enabled each member of the coded set to be identified correctly. The technique described here enables information to be obtained from a bloodstain which relates to an individuals susceptibility to allergens. The usefulness of this information to an investigating officer is discussed.