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The choice of soft or hard tissues to be sampled in case of exhumation of corpses for identification purposes or family relationship testing is based on the degradation conditions of the corpse: the more the corpse is degraded, the less DNA is expected to be retrieved from soft tissue. Therefore, the choice of the "best" tissue samples usually falls on teeth and bones in these “difficult” cases, even though the DNA extraction procedure requires time and effort and it can often result in unexpected, negative results. We here present the results of a daily practice survey that shows that it is possible to obtain good results even on DNA extracted from tissues that appear to be less “appealing” to the examiner by performing “simple” corneal/scleral swabs along with cartilage. While DNA extracted from cartilage has been already described, to our knowledge there is no evidence of publications in the scientific literature dealing with cornea/sclera as a source of DNA in the forensic laboratory. The obtained results demonstrate that it may be advisable to consider other tissues which bear the potential of returning good profile results despite not appearing particularly useful and better control of contamination.

The 2011 collaborative exercise of the ISFG Italian Working Group GeFI was aimed at validating the five ENFSI/EDNAP miniSTR loci D1S1656, D2S441, D10S1248, D12S391 and D22S1045. The protocol required to type at least 50 multilocus profiles from locally resident individuals and two blind bloodstains in duplicate (i.e., using at least two different commercial kits), and to send the electropherograms to the Organizing Committee. Nineteen laboratories distributed across Italy participated, collecting a total of 960 samples. Full concordance was found for the five new miniSTRs as observed from the comparison of 13,150 alleles. The inspection of the electropherograms allowed the identification of a very limited number of mistypings in the miniSTR genotypes thus contributing to the establishment of an high quality Italian database of frequencies.

Twenty X-chromosomal short tandem repeat (STR) loci were typed in 80 families of Italian descent, composed by mother and two or more sons, for a total of 93 meiosis. The analyzed X-STR panel included six clusters of closely linked markers (each spanning3cM): DXS10135-DXS10148-DXS8378 (Xp22); DXS7132-DXS10074-DXS10079 (Xq12); DXS6801-DXS6809-DXS6789 (Xq21); DXS7424-DXS101 (Xq22); DXS10103-HPRTB-DXS10101 (Xq26); DXS8377-DXS10134-DXS7423-DXS10146 (Xq28). Recombination fractions between pairs of markers calculated by pedigree analysis were compared with those obtained from the second-generation Rutgers combined linkage-physical map of the human genome. The observed differences confirm that recombination is not homogeneous along the X chromosome and that the conventional subdivision of X-STRs in four groups of completely unlinked markers cannot be regarded as true. Significant linkage disequilibrium was found between markers DXS6801 and DXS6809 (p=0.017). The effect on likelihood calculations of inferring haplotype frequencies from allele distributions rather than haplotype count in the relevant population was evaluated.

A large number of short tandem repeat (STR) markers spanning the entire human X chromosome have been described and established for use in forensic genetic testing. Due to their particular mode of inheritance, X-STRs often allow easy and informative haplotyping in kinship analyses. Moreover, some X-STRs are known to be tightly linked so that, in combination, they constitute even more complex genetic markers than each STR taken individually. As a consequence, X-STRs have proven particularly powerful in solving complex cases of disputed blood relatedness. However, valid quantification of the evidence provided by X-STR genotypes in the form of likelihood ratios requires that the recombination rates between markers are exactly known. In a collaborative family study, we used X-STR genotype data from 401 two- and three-generation families to derive valid estimates of the recombination rates between 12 forensic markers widely used in forensic testing, namely DXS10148, DXS10135, DXS8378 (together constituting linkage group I), DXS7132, DXS10079, DXS10074 (linkage group II), DXS10103, HPRTB, DXS10101 (linkage group III), DXS10146, DXS10134 and DXS7423 (linkage group IV). Our study is the first to simultaneously allow for mutation and recombination in the underlying likelihood calculations, thereby obviating the bias-prone practice of excluding ambiguous transmission events from further consideration. The statistical analysis confirms that linkage groups I and II are transmitted independently from one another whereas linkage groups II, III and IV are characterised by inter-group recombination fractions that are notably smaller than 50%. Evidence was also found for recombination within all four linkage groups, with recombination fraction estimates ranging as high as 2% in the case of DXS10146 and DXS10134.

We report the case of four women and a man, all born in an Italian village during and immediately after WWII, that recently contacted our laboratory in order to perform kinship analysis. According to their claim, the propositi were the illegitimate offspring of a country gentleman and a peasant woman, given in adoption immediately after birth. A story that curiously reminded us of Jean Jacques Rousseau, Therese Levasseur and their five children. Problems connected with DNA analysis in cases where all stated relationship are questioned, and a wide range of different pedigrees could be used as hypotheses in LR calculations are discussed.

Dropout of the amelogenin Y-specific allele due to an interstitial deletion of the Yp involving the amelogenin Y locus (AMELY) can cause misidentification of sex genotype with potentially serious consequences in personal identification processes and criminal investigations. Inclusion of additional sex-defining markers in forensic DNA typing kits is therefore advisable. In this study, the co-amplification of the sex-determining region Y (SRY) gene and 16 STR loci included in the AmpFlSTR Identifiler PCR Amplification Kit was evaluated. Combination of SRY and Identifiler primers did not compromise the amplification outcome and generated a 90bp male-specific SRY fragment, showing a reproducible peak height ratio in comparison with the AMELY peak. The SRY peak was detectable in presence of amounts of template DNA as low as 125pg, and in mixed samples with a male/female DNA ratio of 1:100.

The presence or absence of genetic heterogeneity in Sicily has long been debated. Through the analysis of the variation of Y-chromosome lineages, using the combination of haplogroups and short tandem repeats from several areas of Sicily, we show that traces of genetic flows occurred in the island, due to ancient Greek colonization and to northern African contributions, are still visible on the basis of the distribution of some lineages. The genetic contribution of Greek chromosomes to the Sicilian gene pool is estimated to be about 37% whereas the contribution of North African populations is estimated to be around 6%. In particular, the presence of a modal haplotype coming from the southern Balkan Peninsula and of its one-step derivates associated to E3b1a2-V13, supports a common genetic heritage between Sicilians and Greeks. The estimate of Time to Most Recent Common Ancestor is about 2380 years before present, which broadly agrees with the archaeological traces of the Greek classic era. The Eastern and Western part of Sicily appear to be significantly different by the χ2-analysis, although the extent of such differentiation is not very high according to an analysis of molecular variance. The presence of a high number of different haplogroups in the island makes its gene diversity to reach about 0.9. The general heterogeneous composition of haplogroups in our Sicilian data is similar to the patterns observed in other major islands of the Mediterranean, reflecting the complex histories of settlements in Sicily.

The distribution of Y-chromosomal single nucleotide polymorphism (SNP) haplogroups and short tandem repeat (STR) haplotypes was determined in a sample of 102 unrelated men of Arab origin from northwestern Algeria (Oran area). A total of nine different haplogroups were identified by a panel of 22 binary markers. The most common haplogroups observed in the Algerian population were E3b2 (45.1%) and J1 (22.5%). Y-STR typing by a 17-loci multiplex system allowed 93 haplotypes to be defined (88 were unique). Striking differences in the allele distribution and gene diversity of Y-STR markers between haplogroups could be found. In particular, intermediate alleles at locus DYS458 specifically characterized the haplotypes of individuals carrying haplogroup J1. All the intermediate alleles shared a common repeat sequence structure, supporting the hypothesis that the variant originated from a single mutational event.

Eight Y-chromosomal short tandem repeats (STRs)-DYS19, DYS389-I, DYS389-II, DYS390, DYS391, DYS392, DYS393 and DYS385 - were typed in a population sample (n = 255) of unrelated Sicilian males from nine different towns on the main island and from the island of Pantelleria. (c) 2005 Elsevier Ireland Ltd. All rights reserved.

Italians residing in Piedmont (Northwest Italy) KEYWORDS: forensic science, DNA typing, population genetics, Piedmont, Italians, D3S1358, TH01, D21S11, D18S51, Penta E, D5S818,D13S317, D7S820, D16S539, CSF1PO, Penta D, vWA, D8S1179, TPOX, FGA Several studies on allelic frequencies of tetrameric STR loci(CODIS loci) in the Italian population have been published; how-ever, data regarding the distribution of recently introduced pen-tameric loci are still scarce.Blood/saliva samples were obtained from 147 unrelated Ital-ians residing in Piedmont (North West Italy). Genomic DNAwasisolated by means of spin columns (Macherey-Nagel, D¨uren,Germany).PCRamplificationwasperformedaccordingtotheman-ufacturer’s instruction using the GenePrint TM R PowerPlex 16 Sys-tem (Promega Corporation, Madison, WI). The amplified productswere detected with the 310 Genetic Analyzer (Applied Biosys-tems, Foster City, CA). Hardy-Weinberg equilibrium was evalu-ated by exact test using the software GENEPOP Version 3.3 (1).

Genotyping of transcribed single nucleotide polymorphisms (SNPs) in cDNA molecules derived from tissue-specific mRNAs has a potential for linking cell types to donors in mixed stains. To test this hypothesis, a single base extension assay targeting the synonymous SNP marker rs857870 in the myeloid cell nuclear differentiation antigen (MNDA) gene was designed. In blood/semen mixtures from donors with informative MNDA genotype (opposite homozygotes), only the MNDA allele of the blood contributor was observed in cDNA, even at blood/semen ratios of 1/20, corresponding to the limit of detection for mixtures by STR profiling. In blood/saliva mixtures, the MNDA allele of the saliva donor was sporadically seen in cDNA, probably due to trace amounts of blood in the donor's saliva, suggesting that the informativeness of the assay may be limited in presence of cell types with partially overlapping mRNA profiles.

Typing of X-chromosomal short tandem repeat (STR) loci in a deficiency paternity case revealed a single Mendelian incompatibility between a female child and her putative grandmother, consisting of an opposite homozygosity at locus DXS8378. The presence of a null allele due to a primer binding site mutation on the child's paternally inherited X chromosome was confirmed by amplification with newly designed DXS8378 external primers. Sequencing analysis showed a point mutation (C>T transition at position 168, according to GenBank accession G08098) in the binding site of the original DXS8378 reverse primer.