Polymerase chain reaction (PCR) amplification and human leukocyte antigen (HLA)-DQ alpha oligonucleotide typing on biological evidence samples: casework experience.

The polymerase chain reaction (PCR) method of specific gene amplification was used in casework to synthesize millions of copies of the polymorphic second exon of the human leukocyte antigen (HLA)-DQ alpha (or DQA1) locus from a variety of evidence samples. The HLA-DQ alpha allelic variants in the amplified deoxyribonucleic acid (DNA) were determined in a rapid non-radioactive test by hybridization to sequence-specific oligonucleotide probes in both the dot-blot and reverse dot-blot formats. This genetic typing system has been subjected to blind proficiency testing; the performance of this test in the analysis of experimentally mixed samples was also evaluated. As of August 1990, over 250 cases have been tested and more than 2000 individual evidence (bloodstains, semen stains, individual hairs, bone fragments, and tissue sections) and reference samples have been analyzed. The first 198 of these cases are summarized in this paper; in 65% of the cases with conclusive results a suspect was included, and in 35%, all suspects were excluded. Individual cases as well as some of the general issues relating to forensic science analysis and this genetic typing system are discussed. The high rate of exclusion reported here combined with the ability of PCR to type old evidence samples suggests the relevance of this genetic test for postconviction review; two cases in which the convicted suspect was excluded are discussed.     

An improved method for complement subcomponent C1R typing

An improved method has been developed for the reliable classification of different C1R genetic variant forms from human serum or plasma. The method combines the use of neuraminidase-digested samples followed by monodimensional isoelectric focusing in the pH range 5 to 8 followed by immunoblotting. The method yields a simple pattern, with one major band in homozygote and two major bands in heterozygote cases.     

IS AGE IMPORTANT? TESTING A GENERAL VERSUS A DEVELOPMENTAL THEORY OF ANTISOCIAL BEHAVIOR*

We tested competing hypotheses derived from Gottfredson and Hirschis (1990) general theory and Moffitt's (1993a) developmental theory of antisocial behavior. The developmental theory argues that different factors give rise to antisocial behavior at different points in the life course. In contrast, the general theory maintains that the factor underlying antisocial behavior (i.e., criminal propensity) is the same at all ages. To test these competing predictions, we used longitudinal data spanning from age 5 to age 18 for the male subjects in the Dunedin Multidisciplinary Health and Development Study. Using reports from three sources (parents, teachers, and the boys themselves), we estimated second-order confirmatory factor models of antisocial behavior. These models provided consistent support for the developmental theory, showing that separate latent factors underlie childhood and adolescent antisocial behavior. Moreover, we found that these childhood and adolescent factors related in ways predicted by Moffitt's developmental theory to four correlates of antisocial behavior: Childhood antisocial behavior was related more strongly than adolescent antisocial behavior to low verbal ability, by per activity, and negative/impulsive personality, whereas adolescent antisocial behavior was related more strongly than childhood antisocial behavior to peer delinquency. The two underlying latent factors also showed the predicted differential relations to later criminal convictions: Childhood antisocial behavior was significantly more strongly associated with convictions for violence, while adolescent antisocial behavior was significantly more strongly associated with convictions for nonviolent offenses.     

Thyreoglobulin and violent asphyxia

The concentration of thyreoglobulin (tg) was determined for death caused by hanging, strangulation by ligature, and throttling. Cases of sudden death (traumatic aortic rupture, penetrating wounds of the heart) were used for comparison. The mean values in cases of hanging (149.9±202.3 ng/ml), strangulation by ligature (193.1±173.3), manual strangulation (561.6±173.9) are distinguishable from violent acute deaths (23.3±27.6) and living healthy individuals (17.3±16.1). By means of statistical comparisons, significant differences were found between throttling and strangulation by ligature and between throttling and hanging (adjusted P<0.001). In connection with examination of the bodies high tg values can be regarded as a vital reaction in obstructive asphyxia.