Which articles and which topics in the forensic sciences are most highly cited?

Forensic science is a multidisciplinary field, which covers many branches of the pure, the applied and the biomedical sciences. Writing-up and publishing research findings helps to enhance the reputation of the investigators and the laboratories where the work was done. The number of times an article is cited in the reference lists of other articles is generally accepted as a mark of distinction. Indeed, citation analysis has become widely used in research assessment of individual scientists, university departments and entire nations. This article concerns the most highly cited papers published in the Journal of Forensic Sciences (JFS) between 1956 and 2005. These were identified with the help of Web-of-Science, which is the on-line version of Science Citation Index, produced by Thomson Institute for Scientific Information (Thomson ISI) with head offices in Philadelphia, USA. This database tracks, among other things, the annual citation records of articles published in several thousand scientific journals worldwide. Those JFS articles accumulating 50 or more citations were identified and rank-ordered according to the total number of citations. These articles were also evaluated according to the name of first author, the subject category of the article, the country of origin and the pattern of co-authorship. This search strategy located 46 articles cited between 50 and 292 times since they first appeared in print. The most highly cited paper by far was by Kasai, Nakamura and White (USA and Japan) concerning DNA profiling and the application of the polymerase chain reaction (PCR) in forensic science. Some forensic scientists appeared as first author on two to three highly cited articles, namely Wetli (USA), Budowle (USA) and Comey (USA). When the highly cited articles were sub-divided into subject category, 15 were identified as coming from toxicology, closely followed by criminalistics (14 articles), pathology (nine articles), physical anthropology (five articles), forensic psychiatry (two articles) and one from odontology. The number of co-authors on these highly cited articles ranged from one to nine and the names of some investigators appeared on as many as four highly cited papers. The vast majority of papers originated from US laboratories although five came from Japan, two each from Sweden and Canada and there was also a joint USA-Swiss collaboration. The Thompson ISI citation databases provide unique tools for tracking citations to individual articles and impact and citation records of scholarly journals.

DYS19 and DYS199 loci in a Chilean population of mixed ancestry

The current Chilean population originated from admixture between aboriginal populations (Amerindians) and Spanish conquerors of European origin. Consequently, the unions that gave rise to the Chilean population were chiefly between Spanish males and aboriginal females, and not the converse. To test the hypothesis that the Y chromosome of the Chilean population is mainly of Spanish origin, while the other chromosomes are from mixed (European and aboriginal) origin, we studied the DYS19 and DYS199 loci in two samples. One sample was obtained from a high socioeconomic stratum, while a second sample was from a low stratum. We studied male blood donors (N = 187) from Santiago, the capital of the country. Subjects were typed for the autosomal ABO and Rh (locus D) blood groups, and for the Y-linked DYS19 and the DYS199 loci, reported as Y-chromosome haplotypes. The aboriginal admixture was estimated for each genetic marker. The percentage of aboriginal admixture was 38.17% for the ABO system and 31.28% for the Rh system in the low socioeconomic stratum and 19.22% and 22.5%, respectively, in the high stratum. Y-chromosome haplotype frequencies constructed from the DYS19 and DYS199 loci demonstrated that the main haplotypes were DYS19*14/DYS199 C, as is often the case with many European populations, and DYS19*13/DYS199 C. The aboriginal admixture from Y-haplotype frequencies was estimated to be 15.83% in the low socioeconomic stratum and 6.91% in the high stratum. These values are lower than the values found using autosomal genetic markers, and are consistent with the historical background of the population studied. This study highlights the population genetic consequences of the asymmetric pattern of genome admixture between two ancestral populations (European and Amerindian).

Molecular analysis of paternity

The unit covers Variable Numbers of Tandem Repeats (VNTR) based paternity analysis as well as the newer methods relying on PCR to analyze sequence-specific polymorphisms and microsatellite regions. The discussion of data analysis and probability calculations has been expanded to address a number of special circumstances, such as the lack of sample from an alleged father, motherless cases, and more.

Genetic population history relationships of the population of Bogotá, Colombia, by using the D1S80, VWA, and TH01 molecular markers

The genetic relationships of the population of Bogotá, Colombia, was comparatively studied with regard to other populations from America, Europe, and Asia, by using the D1S80, VWA, and TH01 molecular loci. From a population history point of view, the population of Bogotá seems to be more related to a European origin, with several differential contributions coming from Amerindians rather than from African and Asian populations, when the D1S80 and TH01 markers were employed. However, the contribution was greater from African populations for the VWA marker. Several explanations are offered to resolve the genetic affiliation of this population.

Overview of human identity testing and forensic genetics

This unit discusses the development of the field of forensic genetics, touching on the quality control and legal issues that are central to this area. It closes with a discussion of some caveats for interpreting forensic DNA results.

D1S80 subtyping by PCR-RFLP: new nomenclature and further characterization

In a previous study, we screened out sequence variations within alleles at the D1S80 locus of a Japanese population using PCR-RFLP with EcoRII as a restriction enzyme. In the present study, through analyzing the alleles in a Chinese population, we were able to demonstrate four new electrophoretic band patterns that were complementary to the Japanese data. After summarizing the band patterns and sequencing results of these two populations, we established a new nomenclature for the PCR-RFLP band patterns, closely relating them to their corresponding sequences so that the new types could be designated easily and accurately. After PCR-RFLP subtyping, nineteen alleles in the Chinese population were revealed to have a total of thirty-seven subtypes. The discrimination power of this locus in the Chinese population was elevated from 0.974 to 0.988, and the Hardy-Weinberg equilibrium in this population showed no deviation when checked. Two samples typed as homozygotes 24/24 and 30/30 were identified to be actually heterozygous according to their band patterns. The result was supported by the sequencing analysis of the two samples in which overlapping of eight and eleven repeat units, respectively, were revealed. The heterozygosity was thus elevated from 0.85 to 0.87. The present study proved that PCR-RFLP was an effective method for subtyping D1S80 alleles in the Chinese.

Northern and southern Croatian population data on seven PCR-based loci

Northern and southern Croatian sample populations were typed at seven PCR-based loci -LDLR, GYPA, HBGG, D7S8, Gc, HLA-DQA1 and D1S80. The results show that all loci meet Hardy-Weinberg expectations and that there is little evidence for association of alleles between loci. Allelic frequency distributions at all loci, except HLA-DQA1, show no differences between the northern and southern Croatian sample populations. Moreover, the population data for Croatians are similar to U.S. Caucasians; only HLA-DQA1 for southern Croatians was statistically different compared with U.S. Caucasians. A Croatian population database(s) has been created and can be used for forensic analyses to estimate the frequency of a multiple locus DNA profile.

Population data on the PCR-based loci LDLR GYPA, HBGG, D7S8, Gc, HLA-DQA1, and D1S80 from Arabs from Dubai

Population data were generated for the loci LDLR, GYPA, HBGG, D7S8, Gc, HLA-DQA1, and D1S80 from 180 Arabs from Dubai. Except for D7S8 (P = 0.003), the genotype frequency distributions for the loci do not deviate from Hardy Weinberg expectations. There was no evidence for departures from expectations of independence between the loci. Using a test for homogeneity, the loci LDLR, GYPA, D7S8, and Gc were similar between the Dubaian Arab population sample and an Arab population sample from Palestine and the occupied territories, while the loci HBGG (P = 0.003), DQA1 (P < 10(-3)), and D1S80 (P = 0.020) were statistically different.

D1S80 allele frequencies in a Chinese population

Allele frequencies for the VNTR locus D1S80 were determined in a Chinese population sample using the polymerase chain reaction and subsequent analysis of the amplified products by polyacrylamide gel electrophoresis and silver staining. A total of 18 nominal D1S80 alleles were observed in 105 unrelated Chinese. The data demonstrate that D1S80 is highly polymorphic in Chinese with a heterozygosity of 90.5%. The D1S80 frequency distribution meets Hardy-Weinberg expectations. This D1S80 data can be used in forensic analyses and paternity tests to estimate the frequency of a DNA profile in a Chinese population.