0000000000763920
AUTHOR
S. Mastrangelo
Caratterizzazione genetica della razza Bracco Francese ed analisi comparative con le principali razze canine
Il sequenziamento del genoma canino ha contribuito a migliorare l’accuratezza delle stime di diversità genetica ed ha anche generato diversi studi sulle relazioni tra le diverse razze allevate (Vaysse et al., 2011; Parker et al., 2017). Tuttavia, alcune razze rimangono ancora poco caratterizzate. È il caso del Bracco Francese tipo Pyrénées. Lo scopo di questo lavoro è stato quello di caratterizzare a livello genomico la razza e studiarne le relazioni con altre razze allevate nel mondo. Sono stati raccolti i campioni di sangue da 48 individui. La genotipizzazione è stata condotta mediante l’Illumina CanineHD BeadChip (173.662 marcatori). Diversi parametri di diversità genetica sono stati cal…
Tracking Zebu Introgression in Mediterranean Cattle Breeds
A recent work investigating genetic origin, admixture and population history of primitive European cattle highlighted, by using genome-wide single nucleotide polymorphisms, zebu gene flow in the Balkan and Italian Podolic cattle populations. Haemoglobin protein polymorphism analysis in Italian breeds highlighted the presence of zebuine markers in both Italian Podolic and Alpine Grey cattle. Based on the above evidences, we here specifically look for genomic regions of zebuine ancestry in a different dataset of 50K genotypes from Mediterranean breeds including 29 Marismena (Spain); 30 Bazadaise and 30 Gasconne (France); 24 Alpine Grey, 97 Piemontese, 51 Chianina, 5 Marchigiana, 121 Romagnola…
Genome-wide homozygosity in Maremmana cattle
The current availability of large numbers of single nucleotide polymorphisms (SNPs) throughout the genome makes these markers particularly suitable for the detection of patterns of genetic diversity and of genome-wide homozygosity in animal populations. The aim of this work was to estimate genetic diversity and homozygosity in the Maremmana cattle breed. We used a sample of 149 animals (males and females) geno-typed with the BovineSNP50 v2 (54K) Illumina BeadChip. After editing for call-rate >0.9 and removing SNP unassigned or on the sex chromosomes, 128 animals and 50,814 SNPs were left. We estimated the following genetic parameters: observed and expected heterozygosity (Ho and He), minor …
Caratterizzazione genomica delle razze bovine autoctone italiane
Negli ultimi cinquant'anni, a causa della sostituzione con le razze cosmopolite, le razze zootecniche locali hanno subito una forte contrazione numerica. Tuttavia, esse rappresentano un’importante patrimonio, in grado, tra le altre cose, di valorizzare ambienti marginali. Sono spesso legate anche a produzioni tipiche di alta qualità. La loro caratterizzazione rappresenta un passo essenziale verso eventuali piani di recupero, conservazione e valorizzazione. Il presente studio è stato condotto al fine di caratterizzare a livello genomico le razze bovine locali allevate in Italia. Sono stati campionati un totale di 814 animali appartenenti a 30 razze italiane e a 2 razze cosmopolite (Charolais…
Genome-wide scan for Runs of Homozygosity in Valle del Belice sheep
The current availability of very large numbers of single nucleotide polymorphisms (SNPs) throughout the genome makes these markers particularly suitable for the detection of genomic regions where a reduction in heterozygosity occurred and offers new opportunities to improve the accuracy of inbreeding (F) estimates. Runs of homozygosity (ROH) are contiguous lengths of homozygous segments of the genome where the two haplotypes inherited from the parents are identical. Here, we investigated the occurrence and the distribution of ROH in medium-density SNP genotypes (~ 50 000) in order to characterize autozygosity in 512 individuals of Valle del Belice sheep and identify the regions of the genom…
Detection of genomic signatures of selection in the North African Brune de l’Atlas cattle
The identification of signatures of selection in indigenous livestock genome is able to elucidate the adaptive mechanisms allowing them to cope with environmental pressures. In the present study, we used genotyping data from 106 Brune de l’Atlas cattle individuals and tests based on the extent of haplotype homozygosity (EHH) to look for footprints of natural selection. We identified 17 genomic regions displaying strong signal of selection (p-value <10-6) overlapping with previously described QTL regions affecting many traits such as meat and milk composition, tuberculosis susceptibility, tick and mastitis resistance. Some of these highly significant candidate regions overlap with four previ…
Application of SNP reduction approaches and random forest for the identification of population informative markers in cosmopolitan and local cattle breeds
In livestock, single nucleotide polymorphism genotyping arrays have been used to differentiate breeds and populations for several downstream applications, including breed allocation of individuals, breeds of origin of crossbred animals, authentication of mono breed products, comparative analyses of selection signatures among several other uses. We already tested a combination of principal component analysis (PCA), used as preselection method, and random forest (RF) used as classification method to assign cosmopolitan Italian breeds with no or very low error rate. In this work, we increased the number of breeds and approaches, to have a more comprehensive view of the strategies available and…
A genome-wide perspective on the population structure of Italian cattle breeds
Despite the growing diffusion of cosmopolite specialized breeds, several autochthonous cattle breeds and populations are still bred in Italy. The aim of this study was to provide a high-resolution picture of the genome-wide diversity and population structure of Italian local cattle breeds using medium-density genome-wide SNP markers. After data editing, the dataset included 800 samples from 32 breeds that were genotyped for 31 013 SNPs. For several breeds we observed a low level of polymorphism and genetic diversity, that together with the small effective population sizes confirmed threat of extinction. According to the runs of homozygosity analysis, evidence of recent inbreeding was strong…
BOVITA: a first overview on genome-wide genetic diversity of Italian autochthonous cattle breeds
Analysis of genomic data is increasingly becoming part of the livestock industry and is an invaluable resource for effective management of breeding programs in small populations. The recent availability of genome-wide SNP panels allows providing background information concerning genome structure in domestic animals, opening new perspectives to livestock genetics. BOVITA was established to join local efforts and resources for the genomic characterization of Italian local cattle breeds. Despite the growing diffusion of some cosmopolite specialized breeds, several autochthonous breeds are still bred in Italy. The main aim of the BOVITA is to investigate the genomic structure of Italian local c…