DNA extraction from soil by EZ1 advanced XL (Qiagen).

EZ1 Advanced XL (Qiagen) is an instrument designed to purify automatically nucleic acids from a wide variety of samples: different protocols for DNA extraction from forensic samples are pre-loaded into special EZ1 Advanced XL DNA Investigator Cards. The present study focuses on DNA extraction from biological samples (blood, saliva, sperm) mixed with 3 different types of soils (loam, silt, sandy), using a modified version of the Manufacturer standard protocol. In order to create several traces in the soil, we used biological samples (blood, saliva, sperm) from known donors. Quantification data, reliability and trends in STRs typing success rates using two different commercial multiplexes were evaluated. EZ1 modified DNA extraction protocol allows to recover DNA free of inhibitors and in good quantity for downstream applications.

DNA analysis from mixed biological materials.

At the crime scene a mixture of biological samples from more than one individual often happens and since generally different contributors may give in the mixture a different contribution of biological material, in this study we have evaluated this effect on STRs analysis.

Detection of STRs from body fluid collected on IsoCode paper-based devices.

Isocode card and IsoCode ID Sample Registration Matrix (Schleicher and Schuell BioScience Inc.) are different paper devices chemically treated that keep sample DNA safe from degradation, allowing for the indefinite storage of DNA at ambient temperatures. In this study, blood was collected on Isocode card while saliva, sperm were collected on IsoCode ID. We also tried to verify the effect of collecting urine on Isocode ID. All samples (belonging to the same male donor) were analyzed after 1 day, 1-5 months since their application on the paper.

Anonymous letters? DNA and fingerprints technologies combined to solve a case.

Two brothers, living in two different cities, received two different anonymous letters. We performed latent prints development and DNA research on the letters and also on a glass used by a cousin suspected to be the letters' sender.

Simultaneous estimation of a Y-specific fragment, an X-specific fragment and sex determination of forensic studies in real-time PCR.

The human sex test in forensic multiplexes is based on the amelogenin gene on both the X and Y chromosomes commonly used in sex genotyping. In this work sex determination across the quantification of nuclear DNA was achieved by real-time PCR of a segment of the X-Y homologous amelogenin (AMG) gene that allowed the simultaneous estimation of a Y- and an X-specific fragment. The AMG real-time PCR design has been used to quantify a set of forensic casework samples.

Rapid and efficacious real-time quantitative PCR assay for quantitation of human DNA in forensic samples.

A reliable quantification of human DNA is necessary in the process of routine forensic human identification. When DNA is degraded, contaminated or associated with inhibitors, is important to accurately estimate the concentration of extracted DNA prior to perform an analysis based on nuclear markers amplified. In this work, a new approaches to DNA quantification employees the use of a real-time fluorescence probe system. The real-time PCR assay is highly sensitive, specific, rapid, cost-effective and flexible assay for analysis of forensic casework samples, can perform with DNA of poor quality and detect specifically amplifiable DNA rather than total DNA for STR analysis.