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Aim Several studies suggest that the N-terminal fragment of pro-brain natriuretic peptide levels are quite different in wild-type transthyretin (TTR)-related amyloidosis (ATTRwt) and mutated TTR-related amyloidosis (ATTRm) compared with immunoglobulin light-chain cardiac amyloidosis. Our aim was to test this hypothesis in a cohort of patients with different types of cardiac amyloidosis. Patients and methods Seventy patients with ATTRwt, ATTRm, and light-chain cardiac amyloidosis matched for left ventricular (LV) mass index were studied by standard echocardiography, tissue Doppler imaging, and plasmatic cardiac biomarkers. Results Despite similar LV mass and renal function, patients with ATTR cardiac amyloidosis showed lower levels of N-terminal fragment of pro-brain natriuretic peptide than do light-chain amyloidosis ones, especially when expressed as a function of LV mass index. Conclusion Amyloidogenic light-chain-derived fibrils induce more severe myocardial dysfunction in light-chain amyloidosis than in ATTR, despite similar myocardial infiltration. Thus, the degree of cardiac dysfunction may be related not only to the amount of amyloid deposited, but also to qualitative differences among fibrils.

The accurate detection of low-allelic variants is still challenging, particularly for the identification of somatic mosaicism, where matched control sample is not available. High throughput sequencing, by the simultaneous and independent analysis of thousands of different DNA fragments, might overcome many of the limits of traditional methods, greatly increasing the sensitivity. However, it is necessary to take into account the high number of false positives that may arise due to the lack of matched control samples. Here, we applied deep amplicon sequencing to the analysis of samples with known genotype and variant allele fraction (VAF) followed by a tailored statistical analysis. This method allowed to define a minimum value of VAF for detecting mosaic variants with high accuracy. Then, we exploited the estimated VAF to select candidate alterations in NF2 gene in 34 samples with unknown genotype (30 blood and 4 tumor DNAs), demonstrating the suitability of our method. The strategy we propose optimizes the use of deep amplicon sequencing for the identification of low abundance variants. Moreover, our method can be applied to different high throughput sequencing approaches to estimate the background noise and define the accuracy of the experimental design.

The etiology and progression of renal carcinomas (RCC) is still poorly understood. RCC have been classified into several pathological entities. The most frequent type, clear cell carcinoma, accounts for about 80% of sporadic RCC and shows several chromosome abnormalities documented both by conventional cytogenetics, loss of eterozygosity (LOH) and replication error (RER) studies. In 10 clear cell type sporadic RCC we evaluated LOH and RER using a set of 10 micro satellite markers covering the chromosome 3p region, which has been suggested for interstitial deletions. Electrophoresis was performed by automated sequencer ABI Prism 377 and data were analyzed with Genescan and Genotyper 2.5 softwares. We revealed allelic loss in 48,7% of informative microsatellites and a single case of RER. We found the highest LOH frequency in 3p25-26 region where maps Von Hippel-Lindau (VHL) oncosuppressor gene. In addition, DNA hypermethylation, an alternative mechanism of VHL gene silencing, was evaluated by methylation-specific PCR. However hypermethylation status was not detected in any of our tumor samples.

Next generation sequencing (NGS) represents the newest approach for massive DNA sequencing. Although this innovative approach is a well-established point in diagnostic genetics, the applicability in forensic field is still limited to sporadic pilot studies. This limit arises from the samples' complexity, in terms of poor quality/quantity ratio, leading to a difficult setting in analytic systems. In this study, first NGS forensic data with a new analytic protocol are presented; data were obtained with a pre-release version of the MiSeq system (Illumina). The system is able to sequence, at the same time, a wide panel including autosomal 63 STRs and 95 SNPs commonly used in forensic practice. In the first part of the study sensitivity and concordance studies were performed by using DNA controls with known genetic profile; also mixtures with different male/female concentrations were analysed, in order to verify the panel performance in comparison with traditional kits. In the second part of the experiment, 60 casework samples coming from different tissues, biological fluids, traces on supports, lysates, different aged/degraded samples were analysed. Bioinformatic analysis was performed with MiSeq FGx System BETA version (Illumina), an innovative software with an easy interface that permits a rapid data interpretation by filtering the big data quantity generated by the instrument. The comparison between new data and genetic profiles obtained with traditional typing on the same samples, the sensitivity and the potential of NGS approach represents an interesting starting point in introducing this innovative approach on forensic genetics scenario.

We describe a novel transthyretin mutation in which phenylalanine is replaced with isoleucine in exon 3 at codon 64: Phe64Ile. The mutation was found in an isolated patient and it was not possible to perform a family study. The phenotype included heart and peripheral nerve involvement associated with a possible gastrointestinal and renal involvement.