Distribution of the minutiae in the fingerprints of a sample of the Spanish population

One of the fundamental aspects of the process of identification through fingerprints is the comparison of the minutiae between the fingermark obtained at the scene of the crime and the suspect's corresponding finger. There is no scientific basis in this process that allows the use of numerical standards, such as those kept in different countries, to obtain the identification. The recent mistakes made in the field of dactyloscopy, together with the growing rigor and scrutiny that forensic evidence undergoes in the legislative and scientific areas, have resulted in the need to reconsider some of the basic principles that support this discipline. A probabilistic estimation of the evidential value is especially necessary; therefore, it is indispensable to know and quantify the variability of the features used in the identification process. The sample studied for this research was obtained from 100 Caucasian men and 100 Caucasian women from the Spanish population, which amounts to a total of 2000 fingerprints. The different types of minutiae were located, identified, and quantified visually on the fingerprint, in four sectors, and inside and outside of a circle, whose radius cut, perpendicularly, fifteen ridges starting from the center cut of the axes that defined the sectors. According to the results obtained in this study, through dactyloscopic identification, the weight of the evidence of a minutia, such as the ridge endings, with frequencies between 55% and 65%, according to the area and gender evaluated, cannot be the same as that of a bifurcation or convergence, with frequencies of 13-18% or those of other minutiae that show frequencies lower than 3%. The significant differences found in the topological distribution of the endings, bifurcations, and convergences show the need to take into account, for its demonstrational value, the finger area in which they are evaluated. The significant association observed between the types of minutiae and the different fingers revealed a greater frequency of endings on the thumb and index fingers, and bifurcations and convergences on the middle, ring, and little fingers.     

Genetic data of 10 X-STRs in a Spanish population sample

In this work, we present population genetic data of 10 X-chromosome STRs (DXS8378, DXS9898, DXS8377, HPRTB, GATA172D05, DXS7423, DXS6809, DXS7132, DXS101 and DXS6789) obtained from sample of 145 unrelated female individuals belonging to Valencia (Spain), a region located in the east of the Iberian Peninsula. All the markers studied present high genetic diversities, similar to those previously reported in other European population samples. No deviations from Hardy-Weinberg equilibrium were observed, with the exception of DXS101 locus. Allele frequencies and parameters of forensic interest for each X-STR were calculated. High mean exclusion chance and power of discrimination values were obtained by combining these 10 X-linked markers. Population comparisons (exact test of population differentiation; pairwise genetic distances) were carried out and low genetic distances were found between our sample and those from other Spanish or European regions.     

Stature estimation from radiographically determined long bone length in a Spanish population sample

The estimation of stature from of a variety of bones is an important aspect of forensic work. In order to obtain reliable results, it is important to have comparative data obtained from the same population group as the skeletal remains. However, lack of up to date information on the population groups of Southern Europe makes the estimation of stature from bones in this area subject to possible error. In this study, the stature of 104 healthy adults from Spain was measured, and an anteroposterior teleradiograph of the right lower and the right upper limb of every subject in the study was made in order to measure the lengths of the femur, tibia, fibula, humerus, cubitus and ulna. Pearson's regression formulae were obtained for both limbs. In males, we found the femur to be the most accurate predictor of stature (R = 0.851), whereas in females best results were obtained with the tibia (R = 0.876).     

Metacarpal sexual determination in a Spanish population

Anthropologists and forensic pathologist determine the sex of skeletons by analyzing quantitative and qualitative characters in the bone remains. Generally, the skull and os coxae are the elements most used, but they are not always preserved. In such cases, the investigator needs to have available other techniques based on different remains. The aim of the present work is to develop and describe discriminating functions for sex determination in a recent Spanish population using metacarpal morphology. A sample of bones corresponding to a contemporary Spanish population deposited at the Complutense University of Madrid (UCM) was analyzed. This sample comprised 697 metacarpals, corresponding to 79 adult individuals (37 men and 42 women). These allowed us to obtain 120 unifactorial discriminant functions. We selected the 10 equations, one for each metacarpal from both hands, that provided the best sexual discrimination. The correct sex classification rank progressed from 81%, for right (R) metacarpals IV and V, to 91%, for left (L) metacarpal II. The results suggest that metacarpals are structures that can be used for sex determination in paleoanthropological and forensic identifications.     

Y-chromosome variation in a Norwegian population sample

Y-chromosome DNA profiles are promising tools in population genetics and forensic science. Here we present DNA profiles of 300 unrelated Y-chromosomes of Norwegian origin. The profile is composed of eight short tandem repeats (STRs) and one single nucleotide polymorphism (SNP). In more than 2/3 of the haplotypes the modular structure in the 5' end of the minisatellite locus DYF155S1 was revealed by minisatellite variant repeat PCR (MVR-PCR) These haplotypes were also typed for deletions of fragment 50f2C (DYF155S2). Allele distribution and paternity exclusion parameters are given for each marker. The degree of haplotype diversity and its implication for statistics are evaluated. In the 300 samples 177 different haplotypes were encountered, of which 137 were observed once only. Analysis showed that the main source of variation is within the population. The Fst values were less than 0.015 in general. Haplotype grouping by the SNP demonstrated two haplogroups (Tat/T and Tat/C). Haplogroup Tat/C--found in 5.7% of the present material - is the same haplogroup as encountered in 60% of Finnish males [Am. J. Hum. Genet. 62 (1998) 1171]. Mutation analysis in 150 father/son pairs (a total of 1200 meiotic events) revealed an average mutation frequency of 0.0042 (95% CI 0.0014-0.0097).     

Mitochondrial diversity of a northeast German population sample

Mitochondrial DNA sequences of the hypervariable regions HV I and HV II were analyzed in 300 unrelated individuals born and living in the northeast corner of Germany (Western Pomerania) to generate a database for forensic identification purposes in this region. Sequence polymorphism were detected using PCR and direct sequencing analysis. A total of 242 different haplotypes were found as determined by 147 variable positions. The most frequent haplotype (263G, 315.1C) was found in 10 individuals and is also the most common sequence in Europe. Three other haplotypes were shared by 5 individuals, 2 sequences by 4, 8 haplotypes by 3, 15 sequences by 2 persons, and 213 sequences were unique. The genetic diversity was estimated to be 0.99 and the probability of two random individuals showing identical mitochondrial DNA (mtDNA) haplotypes is 0.6%. A comparison with other studies from Germany showed only little differences in the distribution of haplogroups. Nevertheless, one frequent haplotype in northeast Germany (five unrelated individuals) could only rarely be found in other German and European regions. Our results may indicate that despite a high admixture proportion in the German population some regions could demonstrate certain characteristic features.     

Human Y-specific STR haplotypes in a Slovenian population sample

The allele distribution of the systems DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS385 and YCAII were investigated in a sample of 121 unrelated males from Slovenia     

Y chromosome STR polymorphisms in a Serbian population sample

Eight Y chromosome short tandem repeat (STR) polymorphisms (DYS19, DYS385, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393) were analyzed in the sample of 114 unrelated males living in Serbia. A general STR allelic frequency pattern in Serbians corresponds to other European populations with the exception of loci DYS19, DYS389II and DYS385. Out of ninety identified haplotypes, 74 (64.91%) appeared in single copies. The most frequent haplotypes (DYS19-DYS385-DYS389I-DYS389II-DYS390-DYS391-DYS392-DYS393) 16-14/15-13-31-24-11-11-13 and 15-15/19-12-28-23-10-12-12 were found in four copies (3.51%). Total haplotype diversity was 0.9947+/-0.0021.     

Y-chromosome STR haplotypes in a southwest Spain population sample

The Y-chromosome polymorphism of eight STRs (DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392; DYS393, DYS385) were studied in 111 unrelated individuals from the population of southwest Spain. The most common haplotype was shared by 3.6% of the sample, while 99 haplotypes were unique. The gene diversity was 0.9977.     

26-Locus Y-STR typing in a Bhutanese population sample

26 Y chromosome short tandem repeat (STR) loci were amplified in a sample of 856 unrelated males from Bhutan, using two multiplex polymerase chain reaction (PCR) assays. The first multiplex is the Y-STR 20plex described by Butler et al. [J.M. Butler, R. Schoske, P.M. Vallone, M.C. Kline, A.J. Redd, M.F. Hammer, A novel multiplex for simultaneous amplification of 20 Y chromosome STR markers, Forensic Sci. Int. 129 (2002) 10-24], and the second is a novel (but overlapping) 14plex that targets six additional Y-STRs (DYS425, DYS434, DYS435, DYS436, DYS461, DYS462) and also amplifies the amelogenin locus. The 26-loci give a discriminating power of 0.9957, though even at this resolution one haplotype occurs 24 times. We identify novel alleles at five loci and microvariants at a further three, which were characterised by sequencing. Extended (11-locus) haplotypes for these samples have been submitted to the Y-STR Haplotype Reference Database (YHRD).     

Permanent teeth development in a Spanish sample. Application to dental age estimation

The purpose of this study is to clarify the chronology of different stages of dental development, according to Demirjian, in a sample of Spanish children, which will enable us to build a database that will be used as a reference in regard to the dental development of individuals of our socio-geographic environment. In the same studied sample, a calculation of the dental age according to Demirjian was carried out. This study was conducted in a final sample consisting of 1010 orthopantograms, corresponding to Spanish children (485 boys and 525 girls) ages 2-16. Comparing the age of onset of the different stages among the children, evidence was found that girls had an earlier general development than boys. These differences were only statistically significant in teeth and concrete stages. The canine teeth revealed greater gender dimorphism, with significant differences in all stages compared with the upper canines. The method proposed by Demirjian for dental age calculation resulted in a significant overestimation of dental age in relation to the chronological age in boys (average of 0.87 years) and girls (average of 0.55 years). Data from this study may be used as reference for dental maturity, as well as a standard for estimating age in Spanish children.     

Analysis of Y-STR loci in a population sample from northeast China

POPULATION: A total of 141 unrelated Chinese Han male individuals living in Liaoning in northeast China.     

Additional variability at the D12S391 STR locus in an Austrian population sample: sequencing data and allele distribution

The highly polymorphic STR locus D12S391 was investigated in an Austrian population sample (N=150) by PCR-amplification, comparative detection on native and denaturing polyacrylamide gels and solid phase single stranded sequencing of three size variant alleles and several additional alleles. A total of 15 alleles, distinguishable by size under denaturing conditions, could be detected. No deviations from Hardy-Weinberg equilibrium were observed in the population investigated (P=0.52). Sequencing of size variants designated 17.3 and 18.3 showed an incomplete (GAT) repeat unit at position two of the tandem region. Additional new sequence variants due to varying compositions of the number of (AGAT) and (AGAC) repeats could be identified. Due to distinct electrophoretical mobilities of alleles of the same size but different sequence structures, denaturing detection conditions should be employed when the aim is standardization.     

Sex assessment from the carpals bones: discriminant function analysis in a 20th century Spanish sample

Sex assessment is one of the first essential steps in human identification, in both medico-legal cases and bio-archaeological contexts. Fragmentary human remains compromised by different types of inhumation or physical insults may frustrate the use of the traditional sex estimation methods, such as the analysis of the skull and pelvis. Currently, the application of discriminant functions to sex unidentified skeletal remains is steadily increasing. However, several studies have demonstrated that, due to variation in size and patterns of sexual dimorphism, discriminant function equations are population-specific [1,2,5,12,61]. In this study, in order to improve sex assessment from skeletal remains and to establish population-specific discriminant functions, the diagnostic values of the carpal bones were considered. A sample of 100 individuals (50 males and 50 females) of known sex and age was analyzed. They belong to a 20th century identified collection from the Municipal Cemetery of "San José", Granada (Spain) and housed in the Laboratory of Anthropology, Faculty of Medicine, University of Granada (Spain). The age of the individuals ranged between 22 and 85 years. Between four and nine measurements of each carpal bone were performed [41,59]. Discriminant function statistics showed a sex assessment accuracy as high as 97.8%. The results suggest that carpal bones can be used for assessing sex in both forensic and bio-archaeological identification procedures.     

Human Y-specific STR haplotypes in the Western Croatian population sample

Nine Y-chromosome STR loci (DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS385 and YCAII) were analysed in a sample of 101 unrelated males from Croatia. Allelic frequencies and gene diversities for each Y-STR locus and haplotype diversity were determined. Ninety-one different haplotypes were obtained from 101 unrelated males and 84 haplotypes were unique. Three most common haplotypes were shared by 3% of the sample, one of them was not found in the online Y-STR Haplotype Reference Database (http://www.ystr.org/).