Component-resolved diagnosis of hazelnut allergy in children

Hazelnuts commonly elicit allergic reactions starting from childhood and adolescence, with a rare resolution over time. The definite diagnosis of a hazelnut allergy relies on an oral food challenge. The role of component resolved diagnostics in reducing the need for oral food challenges in the diagnosis of hazelnut allergies is still debated. Therefore, three electronic databases were systematically searched for studies on the diagnostic accuracy of specific-IgE (sIgE) on hazelnut proteins for identifying children with a hazelnut allergy. Studies regarding IgE testing on at least one hazelnut allergen component in children whose final diagnosis was determined by oral food challenges or a suggestive history of serious symptoms due to a hazelnut allergy were included. Study quality was assessed by the Quality Assessment of Diagnostic Accuracy Studies-2 tool. Eight studies enrolling 757 children, were identified. Overall, sensitivity, specificity, area under the curve and diagnostic odd ratio of Cor a 1 sIgE were lower than those of Cor a 9 and Cor a 14 sIge. When the test results were positive, the post-test probability of a hazelnut allergy was 34% for Cor a 1 sIgE, 60% for Cor a9 sIgE and 73% for Cor a 14 sIgE. When the test results were negative, the post-test probability of a hazelnut allergy was 55% for Cor a 1 sIgE, 16% for Cor a9 sIgE and 14% for Cor a 14 sIgE. Measurement of IgE levels to Cor a 9 and Cor a 14 might have the potential to improve specificity in detecting clinically tolerant children among hazelnut-sensitized ones, reducing the need to perform oral food challenges

genetic diversity and relationship among the three autochthonous sicilian donkey populations assessed by microsatellite markers

AbstractIn the developed countries donkey has lost its main function as draft animal because of the mechanization in agri-culture; as a consequence donkey population was greatly reduced. According to SAVE monitoring institute, three of the eight Italian endangered donkey breeds are native of Sicily (Ragusano, Pantesco, Grigio Siciliano). Urgent safeguard plans are required. The aim of this work is to investigate the distribution of genetic diversity and the relationships among the three Sicilian autochthonous donkey breeds using a set of microsatellite markers. A total of 116 blood samples (61 Ragusano, 39 Pantesco, 16 Grigio Siciliano) were collected in 9 herds all over Sicily. Representative samples of Ragusano and Grigio donkey populations consist of unrelated individuals, whereas the sample of Pantesco represents nearly the entire studbook-registered population managed by "Ispettorato Ripartimentale delle Foreste di Erice (TP)" in the "Azienda S. Matteo". Genomic DNA was amplified at 11 microsatellite..

Protein fraction heterogeneity in donkey's milk analysed by proteomic methods

Donkey's milk is often well tolerate by patients affected by cow's milk protein allergy, probably thanks to its protein composition. This empiric evidence, confirmed by some clinical trials, needs to be better investigated. A preliminary survey on the protein fraction of donkey's milk was carried out: fifty-six individual milk samples have been collected and analysed by IEF and SDS-PAGE. Five different IEF patterns have been identified, showing a marked heterogeneity both in casein and whey protein fractions. A single IEF pattern showed an apparent reduced amount of casein fraction highlighted by SDS. Three of the five IEF patterns have been further investigated by Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-TOF MS)

Mitochondrial DNA control region variation in Sanfratellano horse and two other Sicilian autochthonous breeds

Mitochondrial D-loop hypervariable region was analysed in 20 Sanfratellano and two other Sicilian autochthonous horse breeds (20 Sicilian Oriental Purebred and 20 Sicilian Indigenous) in order to investigate matrilineal genetic diversity. A total of 20 different haplotypes were identified sequencing a fragment of 397 bp; overall, haplotypes showed 31 polymorphic sites (7.8%). High diversity was detected in Sanfratellano (11 haplotypes) and Sicilian Indigenous (13 haplotypes), whereas only one haplotype was found in Sicilian Oriental Purebred. Sanfratellano sequences were compared with those belonging to the other Sicilian autochthonous horses and 118 sequences selected from the GenBank database in order to calculate the statistics of molecular diversity. Six haplotypes were exclusive of Sanfratellano which shares haplotype C, D, H, and O with the Sicilian Indigenous and haplotype U with the Sicilian Oriental Purebred; not significant differentiation was found between Sanfratellano and Sicilian Indigenous. BLAST search showed Sicilian haplotypes overlap with the database sequences but for three. Phylogenetic analysis did not show monophyletic group for Sanfratellano samples or the other breeds included in this analysis

Genome-wide population structure, homozygosity, and heterozygosity patterns of Nero Siciliano pig in the framework of Italian and cosmopolitan breeds

Analysis of genomic data is becoming more and more common for the effective management of livestock breeding programmes, even in the case of local populations. In this work, the genome-wide data of Nero Siciliano pig breed were compared to that of wild boar, Italian local and cosmopolitan breeds to investigate its genetic structure, and runs of homozygosity (ROH) and heterozygosity patterns. The Nero Siciliano has been reported to have the highest rate of genetic diversity among the Italian breeds, and a genetic variability comparable to that of the cosmopolitan breeds. Analyses of genomic structure and relationships underlined its proximity to wild boar, and an internal substructure probably linked to different family lines. The breed showed a low value of inbreeding estimated from ROH, and the highest diversity index among the Italian breeds, even if lower than that of the cosmopolitans. Four ROH islands in three chromosomes (SSC8, SSC11, and SSC14) and one heterozygosity-rich region (SSC1) were identified in Nero Siciliano, highlighting genomic regions related to productive QTL. Across breeds, SSC8 and SSC14 were the chromosomes with most ROH islands, with Mora Romagnola and wild boar showing the highest level of autozygosity. Chromosomes SSC2, SSC6, SSC8 and SSC13 showed the majority of runs of heterozygosity regions, mainly found in the cosmopolitan pig breeds, which reported several genes associated with health-related QTL. The outlined results can help to better identify the genomic profile of this local breed in order to plan matings, maintain adequate internal diversity and exploit the production system

Genetic polymorphisms at candidate genes affecting fat content and fatty acid composition in Modicana cows: effects on milk production traits in different feeding systems.

Feeding greatly affects milk yield and composition. The research is highlighting the potential of genetic polymorphism at some loci to affect milk yield and quality traits. These loci can be up/down regulated depending on the production environment; therefore, we hypothesized that milk yield and composition could differ when cows with different genotype at SCD, DGAT1 and ABCG2 loci are reared in different feeding systems. The polymorphisms of SCD, DGAT1 and ABCG2 genes were investigated in Modicana breed. In all, three polymorphic sites, responsible for the genetic variation of quantitative trait loci and therefore defined quantitative trait nucleotides, were genotyped: the transition g.10329Cgt;T in 5th exon determines a substitution p.A293V in the SCD, the dinucleotide mutation g.10433-10434AAgt;GC in 8th exon responsible for p.K232A substitution in the DGAT1 and the transition g.62569Agt;C in the 14th exon responsible for p.Y581S substitution in the ABCG2 gene. In the sample of 165 Modicana cows, SCD and DGAT1 genes resulted polymorphic; the alleles g.10329T and g.10433-10434GC were the most frequent in SCD and DGAT1 (0.73 and 0.91) respectively, whereas ABCG2 locus was monomorphic for allele A (p.581Y). Sequencing analysis was carried out on 14 samples with different genotypes to confirm the results of the PCR-RFLP protocols. Based on the genotypes at SCD locus, 47 Modicana cows were selected for the nutritional trial: 24 cows in a semi-intensive farm, with 2 h/day grazing on natural pasture, and 23 cows in an extensive farm, with 8 h/day grazing on natural pasture. Monthly, milk yield and composition were evaluated and individual milk samples were analyzed for fatty acids composition by gas chromatography. No differences in milk yield, fat, protein, lactose, casein and urea were associated to SCD genotype. Feeding systems affected milk yield and composition. No significant genotype×feeding system interaction was observed for milk yield and composition. Fatty acids composition was significantly affected only by the feeding system. Significant interactions were found between SCD genotype and feeding system for six fatty acids: 4:0, 6:0, 8:0, 10:0, 12:0 and t11 18:1. We concluded that the feeding system was the factor that mostly affected milk production and composition; moreover, our results do not confirm what reported in literature as regard the effect of the SCD polymorphism on milk fatty acid composition. The high amount of pasture seemed to have resized the SCD polymorphism effects because of the different fatty acids composition of the diet

Genome wide analyses reveal the population distinctiveness of the ‘Nera del Mela’ sheep

Italy has a long history of sheep breeding and counts several local populations that may represent a unique source of genetic diversity. Among these, Nera del Mela is a sheep genetic resource historically reared in Sicily but not officially recognised as a breed. In this study, we genotyped 36 individuals of Nera del Mela using the OvineSNP50K array, in order to estimate the genetic diversity and evaluate the population structure and relatedness with other Italian sheep breeds. Genetic diversity indices, and inbreeding estimated from runs of homozygosity (FROH) revealed a moderate level of variability. Runs of homozygosity islands mapped candidate genes involved in the adaptation to local environment and immune response. Population genetic analyses using different approaches highlighted the hypothesis that this sheep possesses a defined genetic structure, especially if compared with other recognised breeds, despite the influence of other populations such as the Sicilian breeds. Overall, our findings represent a starting point for the possible official acknowledgement of this population, for the creation of a conservation plan, and thus for preserving this genomic heritage.HIGHLIGHTS Nera de Mela sheep can be considered as a reservoir of genetic diversity. The results indicated a clear genetic differentiation from other populations and moderate level of genetic variability. Our findings represent a starting point for the creation of conservation plans

A genome-wide comparison between selected and unselected Valle del Belice sheep reveals differences in population structure and footprints of recent selection

About three decades of breeding and selection in the Valle del Belìce sheep are expected to have left several genomic footprints related to milk production traits. In this study, we have assembled a dataset with 451 individuals of the Valle del Belìce sheep breed: 184 animals that underwent directional selection for milk production and 267 unselected animals, genotyped for 40,660 single-nucleotide polymorphisms (SNPs). Three different statistical approaches, both within (iHS and ROH) and between (Rsb) groups, were used to identify genomic regions potentially under selection. Population structure analyses separated all individuals according to their belonging to the two groups. A total of four genomic regions on two chromosomes were jointly identified by at least two statistical approaches. Several candidate genes for milk production were identified, corroborating the polygenic nature of this trait and which may provide clues to potential new selection targets. We also found candidate genes for growth and reproductive traits. Overall, the identified genes may explain the effect of selection to improve the performances related to milk production traits in the breed. Further studies using high-density array data, would be particularly relevant to refine and validate these results