Search

Recently, there has been much debate about what kinds of genetic markers should be implemented as new core loci that constitute national DNA databases. The choices lie between conventional STRs, ranging in size from 100 to 450 bp; mini-STRs, with amplicon sizes less than 200 bp; and single nucleotide polymorphisms (SNPs). There is general agreement by the European DNA Profiling Group (EDNAP) and the European Network of Forensic Science Institutes (ENFSI) that the reason to implement new markers is to increase the chance of amplifying highly degraded DNA rather than to increase the discriminating power of the current techniques. A collaborative study between nine European and US laboratories was organised under the auspices of EDNAP. Each laboratory was supplied with a SNP multiplex kit (Foren-SNPs) provided by the Forensic Science Service, two mini-STR kits provided by the National Institute of Standards and Technology (NIST) and a set of degraded DNA stains (blood and saliva). Laboratories tested all three multiplex kits, along with their own existing DNA profiling technique, on the same sets of degraded samples. Results were collated and analysed and, in general, mini-STR systems were shown to be the most effective. Accordingly, the EDNAP and ENFSI working groups have recommended that existing STR loci are reengineered to provide smaller amplicons, and the adoption of three new European core loci has been agreed.

The genetic landscape of European Y-chromosomes has been widely surveyed. However, French male lineages are still poorly characterized, being scarce the current genetic contribution to the demographic history of France. We have studied, at Y-chromosome level, French population from 7 different regions throughout France: Nord-Pas-de-Calais (Lille), Bretagne (Rennes), Alsace (Strasbourg), Ile-de-France (Paris), Auvergne (Clermont-Ferrand), Provence-Alpes-Cote d'Azur (Marseille) and Midi-Pyrenees (Toulouse). More than five hundred male samples were genotyped for 27 Y-chromosome biallelic markers and 17 Y-STRs, in order to assess the degree of population sub-structuring of male lineages on this population. The results obtained show a significant level of population sub-structuring when Bretagne was compared with the remaining regions grouping together as a single cluster, obtaining a value of 6.83% ( p =0.0000) for the proportion of the total variance explained by differences between populations, when using Y-SNPs data. Our data will contribute to elucidate the genetic composition of France as well as to reconstruct the demographic history of European populations. Likewise, the population sub-structuring detected entails that special care must be taken when Y-chromosome databases of France are used for forensic casework.

We try to show the utility and possibility to use Y-SNP in forensic genetics. We have selected 27 Y-SNPs distributed in 4 multiplexes. The first step was seeking the minimal DNA quantity to amplify multiplexes and the second step was comparing results from Y-SNP multiplexes with results from a registered trademark Y-STR multiplex using the same sexual assault samples. © 2008 Elsevier Ireland Ltd. All rights reserved.

Based on phylogenetic criteria, we selected 32 mitochondrial DNA (mtDNA) coding region SNPs that allows to distinguish Asian and Native American mtDNA haplogroups. SNP genotyping is carried out in a single multiplex reaction that involves an 18-amplicon PCR amplification, followed by a single minisequencing reaction using SNaPshot. The polymorphisms selected increase the discrimination power of the mtDNA hypervariable regions (HVS-I/II) in populations. Consequently, these combined SNPs are of particular interest in forensic casework, population genetics and clinical research. Here we show preliminary results using a sample from south-east Asia (Taiwan) and Native Americans from Argentina. © 2005.