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MicroRNAs (miRNAs) are a class of non-coding RNAs containing 18-24 nucleotides that are involved in the regulation of many biochemical mechanisms in the human body. The level of miRNAs in body fluids and tissues increases because of altered pathophysiological mechanisms, thus they are employed as biomarkers for various diseases and conditions. In recent years, miRNAs obtained a great interest in many fields of forensic medicine given their stability and specificity. Several specific miRNAs have been studied in body fluid identification, in wound vitality in time of death determination, in drowning, in the anti-doping field, and other forensic fields. However, the major problems are (1) lack of universal protocols for diagnostic expression testing and (2) low reproducibility of independent studies. This review is an update on the application of these molecular markers in forensic biology., Competing Interests: The authors declare no conflict of interest.

Objective: Attacks on humans by dogs in a pack, though uncommon, do happen, and result in severe, sometimes fatal, injuries. We describe the role that canine genetic markers played during the investigation of a fatal dog-pack attack involving a 50-year-old male truck driver in a parking lot in Tuscany (Italy). Using canine specific STR genetic markers, the local authorities, in the course of their investigations, reconstructed the genetic relationships between the dogs that caused the deadly aggression and other dogs belonging to the owner of the parking who, at the moment of the aggression, was located in another region of Italy., Results: From a Bayesian clustering algorithm, the most likely number of clusters was two. The average relatedness among the dogs responsible for the aggression was higher than the average relatedness among the other dogs or between the two groups. Taken together, all these results indicate that the two groups of dogs are clearly distinct. Genetic relationships showed that the two groups of dogs were not related. It was therefore unlikely that the murderous dogs belonged to the owner of the parking lot who, on grounds of this and additional evidence, was eventually acquitted.

Many X-chromosome short tandem repeats (X-STRs) have been validated for forensic use even if further studies are needed on allele frequencies and mutation rates to evaluate the extent of polymorphism in different populations and to establish reference databases useful for forensic applications and for anthropological studies. A single multiplex reaction of seven X-STRs, which includes the DXS6789, HUMARA, DXS10011, DXS7423, HPRTB, DXS6807, DXS101 loci, is presented and their allele frequency distribution in a large population sample including 556 subjects (268 females and 288 males) analysed by five forensic laboratories of Central and Northern Italy is shown. Our results demonstrate the feasibility of a single amplification/detection reaction involving seven markers of the X chromosome, which can be fruitfully used in complex kinship analysis.

Four X-chromosome markers (DXS101, HPRTB, DXS8377, and STRX-1) were typed in a population sample from Tuscany, Italy, using a single amplification reaction. Resolution of a deficiency paternity case involving two women (either they were half-sisters or non-relatives) was made possible by typing these marker in addition to 16 conventional autosomal markers.

Background: The traditional exact method for inferring relationships between individuals from genetic data is not easily applicable in all situations that may be encountered in several fields of applied genetics. This study describes an approach that gives affordable results and is easily applicable; it is based on the probabilities that two individuals share 0, 1 or both alleles at a locus identical by state., Results: We show that these probabilities (zi) depend on locus heterozygosity (H), and are scarcely affected by variation of the distribution of allele frequencies. This allows us to obtain empirical curves relating zi's to H for a series of common relationships, so that the likelihood ratio of a pair of relationships between any two individuals, given their genotypes at a locus, is a function of a single parameter, H. Application to large samples of mother-child and full-sib pairs shows that the statistical power of this method to infer the correct relationship is not much lower than the exact method. Analysis of a large database of STR data proves that locus heterozygosity does not vary significantly among Caucasian populations, apart from special cases, so that the likelihood ratio of the more common relationships between pairs of individuals may be obtained by looking at tabulated zi values., Conclusions: A simple method is provided, which may be used by any scientist with the help of a calculator or a spreadsheet to compute the likelihood ratios of common alternative relationships between pairs of individuals.

A sample of Jews subdivided according to the birth-place of their parents or grand-parents have been examined for a large number of genetic markers in the course of a long-term project on the genetics of Jews. We report here the findings concerning 794 Jews studied for the AHSG polymorphism. All the subsamples were in Hardy-Weinberg equilibrium. A highly significant difference was found between Sephardic + Near East Jews and Ashkenazi (AHSG*2 frequencies: 0.184 +/- 0.015 and 0.258 +/- 0.016, respectively). For comparative purposes the data available on Caucasoids have been considered. It turned out that they were neatly arranged along a latitude-AHSG gene frequency cline (0.0092 of AHSG*2 gene frequency increase per degree of increase of latitude) in the explored 30 degrees-60 degrees range (r = 0.97; P much less than 0.001). Of the two Jewish frequencies that could be taken into consideration because of their sufficient sizes, that of the Near East + Sephardic Jews was perfectly in line with the above mentioned cline, while that of the Ashkenazi was somewhat displaced in the sense of being more similar than expected to the other, more southern, Jewish group. Since the only AHSG*2 frequency significantly displaced from the regression line is that of the Ashkenazi, whose ancestors lived until centuries ago in more southern areas, this finding is a strong confirmation of the observed cline.

The distribution of PLG phenotypes in the population of Tuscany (Central Italy) has been investigated by means of isoelectric focusing followed by immunofixation of desialyzed sera. In a random sample of 383 unrelated healthy blood donors registered at the Hospital of Pisa, three common phenotypes, PLG A, A-B, and B, and two rare variants were found. The allele frequencies calculated in our study were: PLG*A = 0.6749, PLG*B = 0.3225, and PLG*rare = 0.0026. The theoretical exclusion rate in cases of disputed paternity is 17.42%.