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Infectious diseases have large economic impacts on the pig breeding industry worldwide. A few genetic markers associated to disease resistance have been recently identified and used in marker-assisted selection (MAS) in a few pig populations, as part of disease control programs. Neonatal Diarrhea (ND), Post-weaning Diarrhea (PWD), caused by enterotoxigenic E. coli, and Porcine Reproductive and Respiratory Syndrome, caused by PRRS virus (PRRSV), are diseases with high priority for the pig industry. Since interactions or antagonism between growth, innate immunity and disease resistance traits could exist, this work investigated if four disease resistance gene markers [mucin 4 (MUC4), rs338992994 associated with resistance to ND; fucosyltransferase 1 (FUT1), rs335979375 associated with resistance to PWD; and guanylate binding protein 1 (GBP1), rs340943904 and rs80800372 (also known as WUR10000125) associated with resistance to PRRS] could affect seven production traits (average daily gain, back fat thickness, lean meat cuts, feed gain ratio, ham weight, visible intermuscular fat and ham weight loss at first salting) and 15 haematological parameters in about 550 performance tested Italian Large White pigs. We also monitored allele frequencies of the same markers on Italian Large White boars sampled under the national selection breeding program over a 20 years-period. Moreover, we evaluated allele frequencies of these polymorphisms in four Italian local pig breeds (Apulo-Calabrese, Casertana, Cinta Senese and Nero Siciliano). The frequency of the resistance-associated alleles for the four polymorphisms was usually higher in all local pig breeds, indirectly supporting a higher rusticity of autochthonous breeds, compared to commercial populations. The two GBP1 polymorphisms were not in complete linkage disequilibrium in all breeds, except in Apulo-Calabrese. No significant allele frequency change for the investigated markers occurred over 20 years in the Italian Large White boar population in three of these markers. Only FUT1 showed a modest but significant change of allele frequencies over this period. Association analyses carried out in Italian Large White pigs for production traits, meat quality or haematological parameters under investigation showed no significant effect of any genotyped polymorphisms. Our results indicate that implementing MAS programs in Italian Large White pigs with polymorphisms associated with disease resistance have no direct effects on production traits. The selection program running for this heavy pig breed might not negatively impact disease resistance derived by the investigated major genes.

The aim of this work was to analyse the distribution of causal and candidate mutations associated to relevant productive traits in twenty local European pig breeds. Also, the potential of the SNP panel employed for elucidating the genetic structure and relationships among breeds was evaluated. Most relevant genes and mutations associated with pig morphological, productive, meat quality, reproductive and disease resistance traits were prioritized and analyzed in a maximum of 47 blood samples from each of the breeds (Alentejana, Apulo- Calabrese, Basque, Bísara, Majorcan Black, Black Slavonian (Crna slavonska), Casertana, Cinta Senese, Gascon, Iberian, Krškopolje (Krškopoljski), Lithuanian indigenous wattle, Lithuanian White Old Type, Mora Romagnola, Moravka, Nero Siciliano, Sarda, Schwäbisch-Hällisches Schwein (Swabian Hall pig), Swallow-Bellied Mangalitsa and Turopolje). We successfully analyzed allelic variation in 39 polymorphisms, located in 33 candidate genes. Results provide relevant information regarding genetic diversity and segregation of SNPs associated to production and quality traits. Coat color and morphological trait-genes that show low level of segregation, and fixed SNPs may be useful for traceability. On the other hand, we detected SNPs which may be useful for association studies as well as breeding programs. For instance, we observed predominance of alleles that might be unfavorable for disease resistance and boar taint in most breeds and segregation of many alleles involved in meat quality, fatness and growth traits. Overall, these findings provide a detailed catalogue of segregating candidate SNPs in 20 European local pig breeds that may be useful for traceability purposes, for association studies and for breeding schemes. Population genetic analyses based on these candidate genes are able to uncover some clues regarding the hidden genetic substructure of these populations, as the extreme genetic closeness between Iberian and Alentejana breeds and an uneven admixture of the breeds studied. The results are in agreement with available knowledge regarding breed history and management, although largest panels of neutral markers should be employed to get a deeper understanding of the population’s structure and relationships.

Casertana is an endangered autochthonous pig breed (raised in south-central Italy) that is considered to be the descendant of the influential Neapolitan pig population that was used to improve British breeds in the 19th century. Casertana pigs are characterized by a typical, almost complete, hairless phenotype, even though a few Casertana pigs are normal haired. In this work, using Illumina PorcineSNP60 BeadChip data, we carried out a genome-wide association study and an FST analysis with this breed by comparing animals showing the classical hairless phenotype (n = 81) versus pigs classified as haired (n = 15). Combining the results obtained with the two approaches, we identified two significant regions: one on porcine chromosome (SSC) 7 and one on SSC15. The SSC7 region contains the forkhead box N3 (FOXN3) gene, the most plausible candidate gene of this region, considering that mutations in another gene of the same family (forkhead box N1; Foxn1 or FOXN1) are responsible for the nude locus in rodents and alopecia in humans. Another potential candidate gene, rho guanine nucleotide exchange factor 10 (ARHGEF10), is located in the SSC15 region. FOXN3 and ARHGEF10 have been detected as differentially expressed in androgenetic and senescent alopecia respectively. This study on an autochthonous pig breed contributes to shed some light on novel genes potentially involved in hair development and growth and demonstrates that local animal breeds can be valuable genetic resources for disclosing genetic factors affecting unique traits, taking advantage of phenotype variability segregating in small populations.

In this study, we tested the Ion Torrent next generation semiconductor based sequencing technology for meat species identification in several highly processed and complex meat products and meat derived broths (a doner kebab, a beef/pork pate, a meat based filling of tortellini, one instantaneous granular preparation of broth stock made by meat and two ready to use meat broths from different producers). The detection protocol included the sequencing of targeted mitochondrial DNA (mtDNA) regions amplified with universal primer pairs and a bioinformatic pipeline designed to interpret sequencing results. Six libraries were sequenced producing a total of 1,363,351 filtered reads. Data mining detected expected and unexpected meat species in the analysed products. Pork was identified in the kebab and Bubalus bubalis DNA was identified in the beef/pork pate. For products for which the precise meat species ingredient information was not available, it was possible to obtain it. Human contamination based on human detected reads could be useful to evaluate the hygienic level of highly processed products. Mitochondrial haplotypes (mitotypes) were identified for several mtDNA-species combinations providing another level of information useful for the authentication of meat derived products. This work defined a methodological framework to establish assays using this sequencing platform for routine species identification in complex and highly processed food.

In this study, we applied a next generation sequencing (NGS) technology (Ion Torrent) for species identification based on three mitochondrial DNA (mtDNA) regions amplified on DNA extracted from dairy products. Sequencing reads derived from three libraries, obtained from artificial DNA pools or from pooled amplicons, were used to test the method. Then, sequencing results from five libraries obtained from two mixed goat and cow milk samples, one buffalo mozzarella cheese, one goat crescenza cheese and one artisanal cured ricotta cheese, were able to detect all expected species in addition to undeclared species in a few of them. Mining generated reads it was possible to identify different dairy species mitotypes and the presence of human DNA that could constitute a potential marker to monitor the hygienic level of dairy products. Overall results demonstrated the usefulness of NGS for species identification in food products and its possible application for food authentication.

Multidetector computed tomography (MDCT) represents the main source of radiation expo- sure in trauma patients. The radiation exposure of young patients is a matter of considerable medical concern due to possible long-term effects. Multiple MDCT stud- ies have been observed in the young trauma population with an increase in radiation exposure. We have identi- fied 249 young adult patients (178 men and 71 women; age range 14-40 years) who had received more than one MDCT study between June 2010 and June 2014. According to the International Commission on Radio- logical Protection publication, we have calculated the cumulative organ dose tissue-weighting factors by using CT-EXPO software ® . We have observed a mean cumula- tive dose of about 27 mSv (range from 3 to 297 mSv). The distribution analysis is characterised by low effec- tive dose, below 20 mSv, in the majority of the patients. However, in 29 patients, the effective dose was found to be higher than 20 mSv. Dose distribution for the vari- ous organs analysed (breasts, ovaries, testicles, heart and eye lenses) shows an intense peak for lower doses, but in some cases high doses were recorded. Even though cumulative doses may have long-term effects, which are still under debate, high doses are observed in this spe- cific group of young patients.

Nuclear DNA sequences of mitochondrial origin (numts) are derived by insertion of mitochondrial DNA (mtDNA), into the nuclear genome. In this study, we provide, for the first time, a genome picture of numts inserted in the pig nuclear genome. The Sus scrofa reference nuclear genome (Sscrofa10.2) was aligned with circularized and consensus mtDNA sequences using LAST software. A total of 430 numt sequences that may represent 246 different numt integration events (57 numt regions determined by at least two numt sequences and 189 singletons) were identified, covering about 0.0078% of the nuclear genome. Numt integration events were correlated (0.99) to the chromosome length. The longest numt sequence (about 11 kbp) was located on SSC2. Six numts were sequenced and PCR amplified in pigs of European commercial and local pig breeds, of the Chinese Meishan breed and in European wild boars. Three of them were polymorphic for the presence or absence of the insertion. Surprisingly, the estimated age of insertion of two of the three polymorphic numts was more ancient than that of the speciation time of the Sus scrofa, supporting that these polymorphic sites were originated from interspecies admixture that contributed to shape the pig genome.

Casertana is an autochthonous pig breed mainly raised in the Central-South of Italy. This local breed is considered the descendant of the influential Neapolitan breed of the late 18th and 19th centuries. Casertana pigs are characterized by a black or slate-grey coat colour, wrinkled skin, forward ears, two goatlike wattles (not always present) and a typical, almost complete, hairless phenotype.

The domestication process in pigs has fixed different phenotypic and morfological traits in many pig populations as a result of selective breeding towards more productive or differentiated populations from the wild counterparts.

European sea bass (Dicentrarchus labrax) is an important marine species for commercial and sport fisheries and aquaculture production. Recently, the European sea bass genome has been sequenced and assembled. This resource can open new opportunities to evaluate and monitor variability and identify variants that could contribute to the adaptation to farming conditions. In this work, two DNA pools constructed from cultivated European sea bass were sequenced using a next generation semiconductor sequencing approach based on Ion Proton sequencer. Using the first draft version of the D. labrax genome as reference, sequenced reads obtained a total of about 1.6 million of single nucleotide polymorphisms (SNPs), spread all over the chromosomes. Transition/transversion (Ti/Tv) was equal to 1.28, comparable to what was already reported in Salmon species. A pilot homozygosity analysis across the D. labrax genome using DNA pool sequence datasets indicated that this approach can identify chromosome regions with putative signatures of selection, including genes involved in ion transport and chloride channel functions, amino acid metabolism and circadian clock and related neurological systems. This is the first study that reported genome wide polymorphisms in a fish species obtained with the Ion Proton sequencer. Moreover, this study provided a methodological approach for selective sweep analysis in this species.

The identification of the species of origin of meat and meat products is an important issue to prevent and detect frauds that might have economic, ethical and health implications. In this paper we evaluated the potential of the next generation semiconductor based sequencing technology (Ion Torrent Personal Genome Machine) for the identification of DNA from meat species (pig, horse, cattle, sheep, rabbit, chicken, turkey, pheasant, duck, goose and pigeon) as well as from human and rat in DNA mixtures through the sequencing of PCR products obtained from different couples of universal primers that amplify 12S and 16S rRNA mitochondrial DNA genes. Six libraries were produced including PCR products obtained separately from 13 species or from DNA mixtures containing DNA from all species or only avian or only mammalian species at equimolar concentration or at 1: 10 or 1: 50 ratios for pig and horse DNA. Sequencing obtained a total of 33,294,511 called nucleotides of which 29,109,688 with Q20 (87.43%) in a total of 215,944 reads. Different alignment algorithms were used to assign the species based on sequence data. Error rate calculated after confirmation of the obtained sequences by Sanger sequencing ranged from 0.0003 to 0.02 for the different species. Correlation about the number of reads per species between different libraries was high for mammalian species (0.97) and lower for avian species (0.70). PCR competition limited the efficiency of amplification and sequencing for avian species for some primer pairs. Detection of low level of pig and horse DNA was possible with reads obtained from different primer pairs. The sequencing of the products obtained from different universal PCR primers could be a useful strategy to overcome potential problems of amplification. Based on these results, the Ion Torrent technology can be applied for the identification of meat species in DNA mixtures.

Autochthonous pig breeds are usually reared in extensive or semi‐extensive production systems that might facilitate contact with wild boars and, thus, reciprocal genetic exchanges. In this study, we analysed variants in the melanocortin 1 receptor (MC1R) gene (which cause different coat colour phenotypes) and in the nuclear receptor subfamily 6 group A member 1 (NR6A1) gene (associated with increased vertebral number) in 712 pigs of 12 local pig breeds raised in Italy (Apulo‐Calabrese, Casertana, Cinta Senese, Mora Romagnola, Nero Siciliano and Sarda) and south‐eastern European countries (Krškopolje from Slovenia, Black Slavonian and Turopolje from Croatia, Mangalitsa and Moravka from Serbia and East Balkan Swine from Bulgaria) and compared the data with the genetic variability at these loci investigated in 229 wild boars from populations spread in the same macro‐geographic areas. None of the autochthonous pig breeds or wild boar populations were fixed for one allele at both loci. Domestic and wild‐type alleles at these two genes were present in both domestic and wild populations. Findings of the distribution of MC1R alleles might be useful for tracing back the complex genetic history of autochthonous breeds. Altogether, these results indirectly demonstrate that bidirectional introgression of wild and domestic alleles is derived and affected by the human and naturally driven evolutionary forces that are shaping the Sus scrofa genome: autochthonous breeds are experiencing a sort of ‘de‐domestication’ process, and wild resources are challenged by a ‘domestication’ drift. Both need to be further investigated and managed.

Infectious diseases have devastating economic impacts on the pig breeding industry worldwide. A few genetic markers associated with disease resistance have been recently identified and used in Marker Assisted Selection (MAS) in a few pig populations as part of disease control programs.

Runs of homozygosity (ROH) are defined as continuos and uninterrupted chromosome regions in which all loci are homozygous in an individual, even if in the population these loci are not fixed for any allele. ROH are single nucleotide polymorphism (SNP)-derived metrics of autozygosity and provide a DNA based measure of the inbreeding level, as the two homozygous long DNA streches are considered identical by descent (IBD).