Sarah Gino

Development of two multiplex PCR systems for the analysis of 12 X-chromosomal STR loci in a northwestern Italian population sample

Two multiplex polymerase chain reaction systems for the automated profiling of 12 X-chromosomal short tandem repeat (STR) markers were developed. Multiplex A consisted of DXS6789, DXS6809, GATA172D05, DXS101, DXS8378, and DXS8377. Multiplex B consisted of DXS7132, DXS6800, DXS6801, DXS7424, HPRTB, and DXS10011. The set of amplified X-STRs was designed to include groups of closely linked markers (DXS101–DXS7424 and DXS6789–DXS6801–DXS6809) to generate highly informative haplotypes for kinship testing. A population genetics study of the 12 X-STRs was conducted in a northwestern Italian population sample (n=160, 80 women and 80 men). A diallelic pattern at locus DXS6789 was observed in one man.

Differential Greek and northern African migrations to Sicily are supported by genetic evidence from the Y chromosome

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.

Subtyping mtDNA haplogroup H by SNaPshot minisequencing and its application in forensic individual identification

Sequence variation of the hypervariable segments (HVS) I/II of mitochondrial DNA (mtDNA) and the haplogroup affiliation were determined in a sample of 271 Italian subjects. This analysis showed that 42% of the individuals could be ascribed to H, the most frequent haplogroup in European Caucasian populations. This fraction was then screened for specific single nucleotide polymorphisms located in the coding region to identify H subclades H1–H15. We set up two multiplex polymerase chain reactions and specific SNaPshot assays to investigate the frequency distribution of these subgroups in our population sample and to examine their usefulness in discriminating among commonly shared HVS I/II sequences. This allowed the assignment of a large portion of the mtDNAs (∼70%) to specific subhaplogroups, with H1 and H5 being the most represented. About two-thirds of the individuals sharing common HVS I/II sequences were subdivided and ascribed to specific H subhaplogroups with a significant reduction of the frequencies of the most common mtDNA haplotypes. Haplogroup H subtyping could thus be extremely useful in forensic identification when many samples have to be analysed and compared, avoiding excessive time-consuming and labor-intensive sequencing analysis.

Plasmodium falciparum immunodetection in bone remains of members of the Renaissance Medici family (Florence, Italy, sixteenth century).

Medical accounts and ancient autopsy reports imply that tertian malarial fevers caused the death of four members of the Medici family of Florence: Eleonora of Toledo (1522-1562), Cardinal Giovanni (1543-1562), don Garzia (1547-1562) and Grand Duke Francesco I (1531-1587). All members of the Medici family hunted in the endemic malarial areas of Tuscany, such as the marshy areas surrounding their villas and along the swampy Maremma and were, therefore, highly exposed to the risk of being infected by Falciparum malaria. To determine if the original death certificates issued by the court physicians were correct, we carried out immunological investigations and then compared the biological results to the historical sources. Bone samples were examined for the presence of Plasmodium falciparum histidine-rich- protein-2 (PfHRP2) and P. falciparum lactate dehydrogenase (PfLDH) using two different qualitative double-antibody immunoassays. Our findings provide the first modern laboratory evidence of the presence of P. falciparum ancient proteins in the skeletal remains of four members of the Medici family. We confirm the clinical diagnosis of the court physicians, using modern methods. Finally, this study demonstrates that immunodetection can be successfully applied not only to mummified tissues but also to skeletal remains, thus opening new paths of investigation for large archaeological series.

Incestuous paternity detected by STR-typing of chorionic villi isolated from archival formalin-fixed paraffin-embedded abortion material using laser microdissection

ABSTRACT: Microscopic examination of a blood clot expelled by a physically and mentally disabled woman taken to the emergency room because of genital bleeding revealed the presence of chorionic villi encircled by decidua, hemorrhage, and necrosis. In order to identify the father of the product of conception, sections of formalin‐fixed, paraffin‐embedded abortion material were subjected to laser microdissection: DNA extraction from chorionic villi selectively isolated from the surrounding tissues allowed successful STR‐typing of fetal cells, which was otherwise prevented by excess maternal DNA. The large number of homozygous genotypes in the fetal profile suggested incestuous paternity. Analysis of reference DNA samples from male relatives excluded the womans father, paternal grandfather, and maternal grandfather, whereas the obligate paternal alleles of the fetus were constantly present in the genotypes of the womans brother, clearly demonstrating brother–sister incest (probability of paternity >99.99999%).

Northwest Italian Population Data for Thirteen Tetrameric and Two Pentameric STR Loci

ABSTRACT: 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).

Allele frequencies for the PowerPlex 16 STR loci in an Albanian population sample from northern Italy.

In recent years Italy experienced a strong migration flow from Albania: a STR reference database, to be used in forensic casework, was created for the Albanian population. Blood/saliva samples were obtained from 100 unrelated Albanians residing in Piedmont (North West Italy). Genomic DNA was isolated from blood by the Chelex method (1) and from saliva by standard organic phenol/chlorophorm extraction. PCR amplification was performed according to the manufacturers instructions, using the GenePrint™ PowerPlex™ System (Promega Corporation, Madison, WI). The amplified products were detected with the 310 Genetic Analyzer (Perkin-Elmer, Foster City, CA). Hardy-Weinberg equilibrium was evaluated by exact test using the software GENEPOP Version 3.2a (2). The complete data are available to any interested researcher at http://medicina.medfarm.unito.it/dipart/dafml/torre/databasealbanians.htm

LDLR, GYPA, HBGG, D7S8 and GC Allele and Genotype Frequencies in the Northwest Italian Population

Allele and genotype frequencies for five PCR-based DNA markers (LDLR, GYPA, HBGG, D7S8 and GC) were determined in 100 unrelated individuals from Piedmont (Northwest Italy). All five Ioci met Hardy-Weinberg expectations in the sampled population. The combined PD and CE were, respectively, 0.995 and 0.697. Frequencies obtained were compared with other previously published data on Caucasian populations with no significant differences. The genetic data from this study, in addition to those already collected by other groups, contribute to the expansion of the Italian DNA database suitable for forensic casework and paternity testing.

STR typing of fixed human tissue: formalin vs an alcohol-based method

Abstract In this study, we evaluated the effect on DNA typing of storage of human tissue in formalin versus an alcohol-based method (Complucad®). Samples of tissue were collected at different time from fixation. DNA was isolated and, after quantitation, was amplified by quadruplex PCR including four STR loci (LPL, F13B, FESFPS and F13A01). For alcohol-fixed tissue, quantitation showed that DNA yield remained unchanged regardless of storage time and complete profiles were obtained. Instead, the DNA amount recovered from those fixed with formalin was lower and DNA looked very degraded. Actually, for these samples, we observed a lack of amplification of >200 bp loci.

PCR based analyses of epidermal cells found on adhesive tape

Adhesive tapes are commonly used by Police Forces to collect Gun Shot Residues (GSR). In a previous experiment (Torre C. and Gino S., submitted to J. Forensic Sci.) it was observed that enough DNA can be extracted, amplified and typed for the HLA-DQa locus (Saiki et al., 1986), in order to attribute with certainty a GSR stub and/or to obtain samples for DNA analyses.