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Beckwith-Wiedemann syndrome (BWS) is an overgrowth syndrome characterized by fetal macrosomia, macroglossia, and abdominal wall defects. BWS patients are at risk to develop Wilms tumor, neuroblastoma, hepatoblastoma, and adrenal tumors. A young woman with BWS features, but with inconclusive genetic evidence for the disease, came to clinical observation for signs of virilization at the age of 16 years. An adrenocortical tumor was diagnosed and surgically resected. The tumor underwent 2 local relapses that were also surgically treated. The patient was also operated to remove a breast fibroadenoma. SNP arrays were used to analyze chromosome abnormalities in normal and tumor samples from the patient and her parents. The patient presented genome-wide mosaic paternal uniparental disomy (patUPD) both in the adrenocortical and the breast tumors, with different degrees of loss of heterozygosity (LOH). The more recent relapses of the adrenocortical tumor showed a loss of part of chromosome 17p that was absent in the first tumor. Analysis of a skin biopsy sample also showed mosaic patUPD with partial LOH, while no LOH was detected in leukocyte DNA. This case shows that virilizing adrenocortical tumors may be a clinical feature of patients with BWS. The SNP array technology is useful to diagnose genome-wide patUPD mosaicism in BWS patients with an inconclusive molecular diagnosis and underlines the tumorigenic potential of the absence of the maternal genome combined with an excess of the paternal genome.

A collaborative exercise on DNA/RNA co-analysis and RNA cell typing involving 15 GEFI (Italian working group of ISFG) laboratories was organized in collaboration with the Netherlands Forensic Institute. Participants received: 1) PCR primers for a 19-plex mRNA profiling assay, with reference purified PCR products for each cell type targeted in the multiplex; 2) detailed protocols for DNA/RNA co-extraction, mRNA profiling, and interpretation of results; 3) a set of 8 mock forensic stains (7 single source, one a mixture of two body fluids). All but one laboratory generated correct DNA typing results. As expected, stochastic effects were seen for low template DNA extracted from a skin stain. As for mRNA profiling, the percentage of laboratories that correctly identified body fluids was ≥60% for blood, saliva, vaginal mucosa, semen, and skin. Success rates were

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.

Mitochondrial DNA (mtDNA) U/K and J/T are sister haplogroups within the superhaplogroup R. They are both common in Europe, with a combined overall frequency similar to the one reported for H, the most common European haplogroup (40–50%). In this study, we selected 159 Italian subjects, already ascribed to U/K and J/T by RFLP typing, and assigned each mtDNA to specific clades/subclades by investigating at least one diagnostic coding region SNP. For each sister haplogroup, one multiplex PCR and one SNaPshot minisequencing reaction were set up targeting 16 U/K and 7 J/T coding region SNPs. Each mtDNA sample was clearly assigned to a specific subclade, which could be further subdivided into several minor sub-branches according to peculiar HVS I/II motifs. Such a molecular dissection of haplogroups U/K and J/T could be extremely useful to reduce the overall analysis time and labor intensive sequencing procedures in high volume forensic casework, for example when it is important to rapidly exclude samples in order to restrict the number of suspects.