Hypermethioninemia in Campania: Results from 10 years of newborn screening

In the last years tandem mass spectrometry (MS/MS) has become a leading technology used for neonatal screening purposes. Newborn screening by MS/MS on dried blood spot samples (DBS) has one of its items in methionine levels: the knowledge of this parameter allows the identification of infant affected by homocystinuria (cystathionine β-synthase, CBS, deficiency) but can also lead, as side effect, to identify cases of methionine adenosyltransferase (MAT) type I/III deficiency. We started an expanded newborn screening for inborn errors of metabolism in Campania region in 2007. Here we report our ten years experience on expanded newborn screening in identifying patients affected by hypermethioninemia. During this period we screened approximately 77,000 infants and identified two cases: one case of classical homocystinuria and one patient affected by defect of MAT I/III. In this paper we describe these patients and their biochemical follow-up and review the literature concerning worldwide newborn screening reports on incidence of CBS and MAT deficiency

Virus-resistant transgenic plants : benefits, risks and biosafety

Virus-resistant transgenic plants (VRTPs) were first reported two decades ago. However, since the early 1990s, concerns have been raised regarding the potential environmental impact of VRTPs, in particular those which express viral genes. One hypothetical risk is that viral sequences expressed from the transgene could recombine with the genome of a non-target virus, and thus lead to emergence of a novel virus. Recombination between viral RNA and transgene mRNA has already been shown to occur for several viruses under conditions of high selection pressure: when the inoculated virus has been disabled by a genomic deletion. Recent work carried out by the Virology Group at Ca\u2019Tron has focused specifically on cucumoviruses (family Bromoviridae), a genus where viral recombinants have been detected both in the field and laboratory. A sensitive and robust RT-PCR method has been optimized to detect viral recombinants both under conditions of high and low selection pressure, where the virus inoculated is either disabled or wild-type, respectively. Results, under conditions of low selection pressure, showed that those recombinants found in tobacco plants infected with two different cucumoviruses were comparable to those found in tobacco transgenic for part of one cucumovirus genome infected with another cucumovirus. It was therefore concluded that in this specific case novel viral recombinants are not expected to appear. Conditions of high selection pressure for the analysis of recombinants were produced by engineering mutants with six nucleotide deletions at various points along the 3\u2019 non-coding region of Cucumber mosaic virus (CMV) strain I17F. Results so far show an increase in the number of observed recombination sites compared to the low selection pressure study. Detailed studies on and around one of the principal recombination hotspots found (nt 1902) have shown it to be directly involved in the production of a short subgenomic RNA known as RNA5. The RNA structure around hotspot nt 1902 has been determined both in vitro and in silico, with phylogenetic and recombinant analyses identifying its putative role in cucumovirus evolution. It is intended that this study should eventually provide a model for assisting researchers in designing safer viral transgenes, while improving our understanding of the mechanism(s) involved virus RNA recombination, and therefore evolution

Evaluation of the risks that recombination in transgenic plants expressing a viral coat protein gene would lead to the emergence of novel viruses

The development of virus-resistant transgenic plants was one of the early success stories of plant biotechnology. In nearly all cases, resistance has been obtained by expression by the transgenic plant of part of the genome of the target virus, most often a gene coding for the viral coat protein. However, since the early 1990s, there has been concern that these plants could be the source of new viruses. This is because it is well known that viruses exchange genetic information by the means of recombination, and that recombination is an important element contributing to virus evolution and the emergence of viral diseases. But in addition, recombination has also been described in virus-resistant transgenic plants, which in this case occurs between the mRNA of the viral transgene and the RNA of the genome of a virus related to the target virus. For this reason, our recent research has focused on the potential epidemiological impact of recombination in transgenic plants

Evaluation of the risks that recombination in transgenic plants expressing a viral coat protein gene would lead to the emergence of novel viruses

The development of virus-resistant transgenic plants was one of the early success stories of plant biotechnology. In nearly all cases, resistance has been obtained by expression by the transgenic plant of part of the genome of the target virus, most often a gene coding for the viral coat protein. However, since the early 1990s, there has been concern that these plants could be the source of new viruses. This is because it is well known that viruses exchange genetic information by the means of recombination, and that recombination is an important element contributing to virus evolution and the emergence of viral diseases. But in addition, recombination has also been described in virus-resistant transgenic plants, which in this case occurs between the mRNA of the viral transgene and the RNA of the genome of a virus related to the target virus. For this reason, our recent research has focused on the potential epidemiological impact of recombination in transgenic plants