Altered TDP-43-dependent splicing in HSPB8-related distal hereditary motor neuropathy and myofibrillar myopathy.

BACKGROUND AND PURPOSE: Mutations in the small heat-shock protein 22 gene (HSPB8) have been associated with Charcot-Marie-Tooth disease type 2L, distal hereditary motor neuropathy (dHMN) type IIa and, more recently, distal myopathy/myofibrillar myopathy (MFM) with protein aggregates and TDP-43 inclusions. The aim was to report a novel family with HSPB8K141E -related dHMN/MFM and to investigate, in a patient muscle biopsy, whether the presence of protein aggregates was paralleled by altered TDP-43 function. METHODS: We reviewed clinical and genetic data. We assessed TDP-43 expression by qPCR and alternative splicing of four previously validated direct TDP-43 target exons in four genes by reverse transcriptase-polymerase chain reaction. RESULTS: The triplets and their mother presented in the second to third decade of life with progressive weakness affecting distal and proximal lower limb and truncal muscles. Nerve conduction study showed a motor axonal neuropathy. The clinical features, moderately raised creatin kinase levels, selective pattern of muscle involvement on magnetic resonance imaging and pathological changes on muscle biopsy, including the presence of protein aggregates, supported the diagnosis of a contemporary primary muscle involvement. In affected muscle tissue we observed a consistent alteration of TDP-43-dependent splicing in three out of four TDP-43-target transcripts (POLDIP3, FNIP1 and BRD8), as well as a significant decrease of TDP-43 mRNA levels. CONCLUSIONS: Our study confirmed the role of mutated HSPB8 as a cause of a combined neuromuscular disorder encompassing dHMN and MFM with protein aggregates. We identified impaired RNA metabolism, secondary to TDP-43 loss of function, as a possible pathological mechanism of HSPB8K141E toxicity, leading to muscle and nerve degeneration.

Analysing and exemplifying forensic conclusion criteria in terms of Bayesian decision theory.

There is ongoing discussion in forensic science and the law about the nature of the conclusions reached based on scientific evidence, and on how such conclusions - and conclusion criteria - may be justified by rational argument. Examples, among others, are encountered in fields such as fingermarks (e.g., 'this fingermark comes from Mr. A's left thumb'), handwriting examinations (e.g., 'the questioned signature is that of Mr. A'), kinship analyses (e.g., 'Mr. A is the father of child C') or anthropology (e.g., 'these are human remains'). Considerable developments using formal methods of reasoning based on, for example (Bayesian) decision theory, are available in literature, but currently such reference principles are not explicitly used in operational forensic reporting and ensuing decision-making. Moreover, applied examples, illustrating the principles, are scarce. A potential consequence of this in practical proceedings, and hence a cause of concern, is that underlying ingredients of decision criteria (such as losses quantifying the undesirability of adverse decision consequences), are not properly dealt with. There is merit, thus, in pursuing the study and discussion of practical examples, demonstrating that formal decision-theoretic principles are not merely conceptual considerations. Actually, these principles can be shown to underpin practical decision-making procedures and existing legal decision criteria, though often not explicitly apparent as such. In this paper, we will present such examples and discuss their properties from a Bayesian decision-theoretic perspective. We will argue that these are essential concepts for an informed discourse on decision-making across forensic disciplines and the development of a coherent view on this topic. We will also emphasize that these principles are of normative nature in the sense that they provide standards against which actual judgment and decision-making may be compared. Most importantly, these standards are justified independently of peoples' observable decision behaviour, and of whether or not one endorses these formal methods of reasoning.

The meaning of justified subjectivism and its role in the reconciliation of recent disagreements over forensic probabilism.

In this paper we reply to recent comments in this Special Issue according to which subjective probability is not considered to be a concept fit for use in forensic evaluation and expert reporting. We identify the source of these criticisms to lie in a misunderstanding of subjective probability as unconstrained subjective probability; a lack of constraint that neither corresponds to the way in which we referred to subjective probability in our previous contributions, nor to the way in which probability assignment is understood by current evaluative guidelines (e.g., of ENFSI). Specifically, we explain that we understand subjective probability as a justified assertion, i.e. a conditional assessment based on task-relevant data and information, that may be thought of as a constrained subjective probability. This leads us to emphasise again the general conclusion that there is no gap between justified (or, reasonable) subjective probability and other concepts of probability in terms of its ability to provide assessments that are soundly based on whatever relevant information available. We also note that the challenges an expert faces in reporting probabilities apply equally to all interpretations of probability, not only to subjective probability.

The consequences of understanding expert probability reporting as a decision.

In this paper we reiterate that the personalist interpretation of probability is inevitable and as least as informed as any other allegedly more 'objective' definition of probability. We also argue that the problem faced by forensic scientists, the reporting on imperfect personal knowledge, in terms of probabilities, can be reconstructed as a decision problem. Tackling this problem through a rigorous decision theoretic analysis provides further argument in support of the view that optimal probability reporting is in terms of single numbers, not intervals.

Reframing the debate: A question of probability, not of likelihood ratio.

Evidential value is measured by a likelihood ratio. This ratio has two components, the probability, or probability density, of the evidence if the prosecution proposition is true and the probability (density) of the evidence if the defence proposition is true. It takes the form of a single value, even if these probabilities are subjective measures of belief of the reporting forensic scientist.

Boys who are born preterm show a relative lack of fat-free mass at 5 years of age compared to their peers.

AIM: Prematurity is associated with features of metabolic syndrome in young adulthood. We investigated the body composition and blood pressure of children born preterm. METHODS: A longitudinal, observational study was conducted with preterm infants who had a birth weight of <1500 g and a gestational age of <32 weeks. Growth and body composition were assessed by air displacement plethysmography at term equivalent age and at school age and were compared to those of 61 healthy, term breastfed subjects. RESULTS: A total of 63 preterm infants were enrolled. At term equivalent age, growth and fat-free mass were lower in preterm infants than in term newborns, but fat mass was higher. At 5 years of age, children born preterm were still lighter and shorter than children born at term. When the results were analysed by gender, the fat-free mass index was lower in boys born preterm than in their peers (12.1 ± 1.1 versus 13.0 ± 1.0 kg/h(2) p < 0.005), whereas no difference was detected among girls. Diastolic blood pressure was higher in children born preterm than in children born at term (61.14 ± 7.8 vs 56.69 ± 8.2 mmHg, p = 0.009). CONCLUSION: Boys born preterm showed a relative lack of fat-free mass at school age compared to their peers.

The importance of distinguishing information from evidence/observations when formulating propositions.

The value of forensic results crucially depends on the propositions and the information under which they are evaluated. For example, if a full single DNA profile for a contemporary marker system matching the profile of Mr A is assessed, given the propositions that the DNA came from Mr A and given it came from an unknown person, the strength of evidence can be overwhelming (e.g., in the order of a billion). In contrast, if we assess the same result given that the DNA came from Mr A and given it came from his twin brother (i.e., a person with the same DNA profile), the strength of evidence will be 1, and therefore neutral, unhelpful and irrelevant(1) to the case at hand. While this understanding is probably uncontroversial and obvious to most, if not all practitioners dealing with DNA evidence, the practical precept of not specifying an alternative source with the same characteristics as the one considered under the first proposition may be much less clear in other circumstances. During discussions with colleagues and trainees, cases have come to our attention where forensic scientists have difficulty with the formulation of propositions. It is particularly common to observe that results (e.g., observations) are included in the propositions, whereas-as argued throughout this note-they should not be. A typical example could be a case where a shoe-mark with a logo and the general pattern characteristics of a Nike Air Jordan shoe is found at the scene of a crime. A Nike Air Jordan shoe is then seized at Mr A's house and control prints of this shoe compared to the mark. The results (e.g., a trace with this general pattern and acquired characteristics corresponding to the sole of Mr A's shoe) are then evaluated given the propositions 'The mark was left by Mr A's Nike Air Jordan shoe-sole' and 'The mark was left by an unknown Nike Air Jordan shoe'. As a consequence, the footwear examiner will not evaluate part of the observations (i.e., the mark presents the general pattern of a Nike Air Jordan) whereas they can be highly informative. Such examples can be found in all forensic disciplines. In this article, we present a few such examples and discuss aspects that will help forensic scientists with the formulation of propositions. In particular, we emphasise on the usefulness of notation to distinguish results that forensic scientists should evaluate from case information that the Court will evaluate.

Consensus paper: pathological mechanisms underlying neurodegeneration in spinocerebellar ataxias.

Intensive scientific research devoted in the recent years to understand the molecular mechanisms or neurodegeneration in spinocerebellar ataxias (SCAs) are identifying new pathways and targets providing new insights and a better understanding of the molecular pathogenesis in these diseases. In this consensus manuscript, the authors discuss their current views on the identified molecular processes causing or modulating the neurodegenerative phenotype in spinocerebellar ataxias with the common opinion of translating the new knowledge acquired into candidate targets for therapy. The following topics are discussed: transcription dysregulation, protein aggregation, autophagy, ion channels, the role of mitochondria, RNA toxicity, modulators of neurodegeneration and current therapeutic approaches. Overall point of consensus includes the common vision of neurodegeneration in SCAs as a multifactorial, progressive and reversible process, at least in early stages. Specific points of consensus include the role of the dysregulation of protein folding, transcription, bioenergetics, calcium handling and eventual cell death with apoptotic features of neurons during SCA disease progression. Unresolved questions include how the dysregulation of these pathways triggers the onset of symptoms and mediates disease progression since this understanding may allow effective treatments of SCAs within the window of reversibility to prevent early neuronal damage. Common opinions also include the need for clinical detection of early neuronal dysfunction, for more basic research to decipher the early neurodegenerative process in SCAs in order to give rise to new concepts for treatment strategies and for the translation of the results to preclinical studies and, thereafter, in clinical practice.

Identification of a common mutation in the carnitine palmitoyltransferase II gene in familial recurrent myoglobinuria patients.

Carnitine palmitoyltransferase (CPT) II deficiency is the most common inherited disorder of lipid metabolism affecting skeletal muscle. We have identified a missense mutation (Ser113Leu) in one patient with the classical muscular symptomatology. Transfection experiments in COS cells demonstrate that the mutation drastically depresses the catalytic activity of CPT II. The mutation results in normal synthesis but a markedly reduced steady-state level of the protein, indicating decreased stability of mutant CPT II. The Ser113Leu mutation is the most frequent cause of CPT II deficiency. The mutation can be detected easily by restriction analysis enabling molecular diagnosis of most patients and identification of heterozygous carriers.

[Effect of prematurity on fat mass distribution and blood pressure at prepubertal age: a follow-up study]. / Effetto della prematurità sulla distribuzione della massa grassa e sulla pressione arteriosa in età prepubere: studio di follow-up.

OBJECTIVES: Preterm infants may develop altered adiposity, a risk factor for metabolic syndrome. The aim was to evaluate if body composition and blood pressure were altered in a cohort of children born preterm followed up to prepubertal age. METHODS: Observational, longitudinal, explorative study. Forty children born preterm underwent growth and body composition assessment by an air displacement plethysmography system at term c.a. and at 5 years. BMI, skinfold thicknesses and blood pressure were further measured at 5 years. Inclusion criteria were birth weight <1500 g and gestational age <32 weeks. Exclusion criteria were congenital/chromosomal or surgical diseases. Forty-three healthy children born at term were the reference group. RESULTS: At term c.a. preterm children were lighter (2455 +/- 484 g vs 3247 +/- 345 g; p<0.001) and shorter (45.6 +/- 3.4 cm vs 49.1 +/- 2.3 cm; p<0.001) than children born at term and their fat mass was higher (14.8% vs 8.6%; p=0.02). At 5 years of life, weight and height of children born preterm were lower than those of their counterpart (18.328 +/- 3.01 vs 20.302 +/- 3.01 g; p=0.008 and 109.7 +/- 6.5 vs 112.7 +/- 4.3 cm; p=0.02, respectively). No difference in percentage of fat mass was detected. Abdominal, subscapular and suprailiac skinfolds (mm) were larger in the preterm group (6.9 +/- 3.6 vs 5.3 +/- 2.8, p=0.002; 6.5 +/- 2.8 vs 5.0 +/- 1.6, p=0,01 and 11.8 +/- 4.3 vs 9.3 +/- 3.8, p=0,01, respectively). Diastolic pressure (mmHg) was higher in the preterm group (62.2 vs 57.5, p=0.01). CONCLUSIONS: At prepubertal age children born preterm tend towards a greater truncal adiposity and increased values of diastolic pressure which might have adverse consequences for later health.

DNA transfer when using gloves in burglary simulations.

Several studies have demonstrated that DNA can be indirectly transferred from an individual onto a surface. Therefore, the presence of DNA that is compatible with a given person does not necessarily mean that this person has touched the surface on which the DNA was recovered. The present work simulates cases, where DNA is recovered on a door handle and compared to several reference DNA profiles. The DNA profile of the trace shares DNA components with a person of interest (POI). When asked about the DNA results, the POI says he has nothing to do with the incident and has never been at the scene. However, a possibility would be that the DNA came from his recently stolen gloves. Someone else, the alternative offender (AO), could have opened the door wearing his gloves (POI's gloves), and transferred his DNA (POI's DNA). Based on the above-mentioned scenario, 60 burglary simulations experiments were carried out to generate data to assess DNA results given these allegations. The quantity and quality of DNA profiles (NGM SElect) recovered when the POI opened/closed the door bare-handed or when someone else performed the same activity but using POI's gloves, were compared. The gloves were regularly worn during at least three months by their owner during the winter. On the contrary, the AO wore them only for two minutes. Among the traces collected on the door handles, less than 50% of the traces led to interpretable DNA profiles. In 30% of the cases (3/10), when the door was opened/closed with bare hands, the DNA found on the door handle led to a mixed DNA profile with the POI's DNA aligning with the major contributor. For the experiments where the AO opened/closed the door with the POI's gloves, the POI's DNA was compatible with 22% (11/50) of the mixed DNA profile, aligning with the major in 8% of the cases (4/50). The DNA profiles of the offices' occupants were observed on the door handles, but not the AO's. In addition to the results of the experiments, we show two examples of how one can assess results observed in casework. Given the possibility of indirect transfer of minute DNA quantities, this research emphasizes the need to evaluate DNA results given the activities when the POI has a legitimate reason that can explain the presence of their DNA.

Learning about Bayesian networks for forensic interpretation: an example based on the 'the problem of multiple propositions'.

Both, Bayesian networks and probabilistic evaluation are gaining more and more widespread use within many professional branches, including forensic science. Notwithstanding, they constitute subtle topics with definitional details that require careful study. While many sophisticated developments of probabilistic approaches to evaluation of forensic findings may readily be found in published literature, there remains a gap with respect to writings that focus on foundational aspects and on how these may be acquired by interested scientists new to these topics. This paper takes this as a starting point to report on the learning about Bayesian networks for likelihood ratio based, probabilistic inference procedures in a class of master students in forensic science. The presentation uses an example that relies on a casework scenario drawn from published literature, involving a questioned signature. A complicating aspect of that case study - proposed to students in a teaching scenario - is due to the need of considering multiple competing propositions, which is an outset that may not readily be approached within a likelihood ratio based framework without drawing attention to some additional technical details. Using generic Bayesian networks fragments from existing literature on the topic, course participants were able to track the probabilistic underpinnings of the proposed scenario correctly both in terms of likelihood ratios and of posterior probabilities. In addition, further study of the example by students allowed them to derive an alternative Bayesian network structure with a computational output that is equivalent to existing probabilistic solutions. This practical experience underlines the potential of Bayesian networks to support and clarify foundational principles of probabilistic procedures for forensic evaluation.

[Intra-abdominal adiposity in preterm infants: an explorative study]. / Adiposità intra-addominale in nati pretermine: studio esplorativo.

OBJECTIVE: The aim of the present study was to compare the total body fat mass and the intra-abdominal adipose tissue between preterm infants assessed at term corrected age and full-term newborns. METHODS: An observational explorative study was conducted. 25 preterm and 10 full term infants were evaluated at 0-1 month of corrected and postnatal age, respectively. The total body fat mass was assessed by means of an air displacement plethysmography system (Pea Pod COSMED, USA) and the intra-abdominal adipose tissue by means of magnetic resonance imaging (software program SliceOMatic, Version 4.3,Tomovision, Canada). RESULTS: Total body fat mass (g) of preterm and term infants was 633 (+/- 183) and 538 (+/- 203) respectively while intra-abdominal fat mass (g) was 14.2 (+/- 4.9) and 19.9 (+/- 11.4). CONCLUSIONS: Preterm infants, although exhibiting a total body fat mass higher than full term infants, do not show an increased intra-abdominal adipose tissue.

A probabilistic approach to evaluate salivary microbiome in forensic science when the Defense says: `It is my twin brother'.

Salivary microbiota profiles may represent a valid contribution to forensic investigation when standard DNA genotyping methods fail. Starting from questioned and control materials in the form of saliva, the evidence can be expressed by means of a distance between those materials taking into account specific aspects of the microbiota composition. The value of the evidence for forensic discrimination purposes is quantified by means of a Bayes' factor, that allows one to overcome the major limitations and pitfalls of intuition connected to the use of cut-off values as a mean of decision.

Predictive genetic tests in neurodegenerative disorders: a methodological approach integrating psychological counseling for at-risk individuals and referring clinicians.

The identification of the molecular basis of numerous hereditary neurological disorders allowed the feasibility of predictive genetic tests for at-risk family members. In agreement with international guidelines, we tested a protocol for a predictive test to optimize cooperation among specialists, well-being of participants, and organization of clinical activities. The psychiatrist/psychologist did not meet the at-risk subjects, but cooperated with the team, integrating psychological support for participants and clinicians. We enrolled 60 subjects at risk for Huntington disease, and 32 at risk for spinocerebellar ataxias. Seventy-two subjects (78%) continued the visit program; 55 (60%) received the genetic result, and 38 subjects (41%) completed the program. Participation and outcome were similar in both groups. Mean psychological scores were all below significant levels; however, the need for psychological support was recognized for 5 mutation carriers and a non-carrier. Our data provide a methodological example of a simple and safe procedure for a predictive test, and indicate that the clinical conference represents a good setting to handle psychosocial impact associated with disclosure of genetic results in hereditary late-onset disorders.

[Chagas disease in a non endemic country: a study in the district of Bologna (Italy). Multidisciplinary analysis of the disease in the Latin American migrant population]. / La malattia di Chagas in un paese non endemico: il conte- sto bolognese. Analisi multidisciplinare della malattia e del fenomeno migratorio.

Chagas disease is a parasitic illness endemic in 21 countries of Central and South America, affecting over 10 million people. Due to the increase of migration flows to Europe, Chagas disease is an emerging public health issue in non endemic countries. In Italy, where no specific policy has yet been developed, the Centre for International Health of the University of Bologna is carrying out the project "Chagas disease in a non endemic country: a study in the district of Bologna". A multidisciplinary and multi-method approach was adopted to estimate the problem and its impact in our territory. A retrospective analysis was performed searching several databases in order to collect information concerning the demographic and epidemiological profile of Latin American migrants coming from endemic countries. At the same time, a preliminary ethnographic research was conducted to start unveiling the main socio-anthropological characteristics of this population, thanks to the involvement of key informants and community associations. According to preliminary findings, Chagas disease is a present and possibly increasing reality in our territory. Due to the particular features of the affected population, socio-cultural variables have to be considered for their impact on the visibility of the condition and on health seeking behaviors.

High frequency of TARDBP gene mutations in Italian patients with amyotrophic lateral sclerosis.

Recent studies identified rare missense mutations in amyotrophic lateral sclerosis (ALS) patients in the TARDBP gene encoding TAR DNA binding protein (TDP)-43, the major protein of the ubiquitinated inclusions (UBIs) found in affected motor neurons (MNs). The aim of this study was to further define the spectrum of TARDBP mutations in a large cohort of 666 Italian ALS patients (125 familial and 541 sporadic cases). The entire coding region was sequenced in 281 patients, while in the remaining 385 cases only exon 6 was sequenced. In 18 patients, of which six are familial, we identified 12 different heterozygous missense mutations (nine novel) all locating to exon 6, which were absent in 771 matched controls. The c.1144G>A (p.A382T) variation was observed in seven patients, thus representing the most frequent TARDBP mutation in ALS. Analysis of microsatellites surrounding the TARDBP gene indicated that p.A382T was inherited from a common ancestor in 5 of the 7 patients. Altogether, the frequency of TARDBP gene mutations appears to be particularly high in Italian ALS patients compared to individuals of mainly Northern European origin (2.7% vs. 1%). Western blot analysis of lymphocyte extracts from two patients carrying the p.A382T and p.S393L TARDBP mutations showed the presence of lower molecular weight TDP-43 bands, which were more abundant than observed in healthy controls and patients negative for TARDBP mutations. In conclusion, this report contributes to the demonstration of the causative role of the TARDBP gene in ALS pathogenesis and indicates that mutations may affect the stability of the protein even in nonneuronal tissues.

[Early nutrition: the role of genetics and epigenetics]. / Nutrizione nelle prime epoche della vita: ruolo della genetica e dell' epigenetica.

Many adult diseases seem to be associated with early nutrition and the subsequent growth pattern. Epidemiological studies hypotized that babies with intrauterine and/or neonatal growth retardation may be at greater risk of metabolic syndrome later in life. According to the Barker's "thrifty phenotype hypotesis" early malnutrition, whereas inducing physiological compensation by the promotion of early survival, appears to confer greater susceptibility to adults diseases. Epigenetics, that is the interindividual variation in DNA methylation patterns and chromatin remodelling, provide a potential explanation for how environmental factors can modify the risk for development of many common diseases. Beginning from animal models, many studies concerning early nutrition, epigenetic modifications and genes expression have been carried out. Maternal undernutrition during pregnancy, especially in the peri-implantation period, not only causes a prolonged growth retardation but also modifies the programming of biochemical mechanisms related to endocrine-metabolic control. Human studies have demonstrated the role played by IGF-1 as indicator of nutritional status and fetal/postnatal growth retardation. It has been reported that alterations in IGF axis, which predispose to adults diseases, may be due to an alterated epigenetic regulation that can modify IGF expression. Despite the critical inter-relation between early nutrition, growth, development, and subsequent health, there are few data on the influence of early nutrition on the modifications of the epigenetic gear. Furthermore it is hoped for a bigger attention to the early nutrition to prevent the development of diseases later in life.

More on the question 'When does absence of evidence constitute evidence of absence?' How Bayesian confirmation theory can logically support the answer.

In forensic science it is not rare that common sayings are used to support particular inferences. A typical example is the adage 'The absence of evidence is not evidence of absence'. This paper analyzes the rationale hidden behind such statement and it offers a structural way to approach the analysis of this particular adage throughout a careful analysis of four different scenarios.