Search results for "Polymorphism"
showing 10 items of 1968 documents
Genetic and protein polymorphism at CSN1S1 locus in two goat breeds.
2006
Genetic polymorphisms of casein have received a considerable research effort for many years because of its potential effect on milk composition. Milk composition, specifically protein content, differs quantitatively and qualitatively among species and also among breeds and individuals. Sicilian goat breeds seem to be an interesting model since they have never been under a selection program, and therefore may carry unique casein polymorphisms. Moreover, the importance of goat milk in infant diets is growing probably because goat milk in some cases is less allergenic than cow milk. It is important to evaluate the genetic polymorphisms at the CSN1S1 locus in the populations of interest, like t…
Genetic diversity and phylogenetic relationships among four breeds reared in Sicily using β-lactoglobulin promoter region polymorphisms
2011
The aim of this work was to analyze the genetic diversity and the phylogenetic relationships among the Valle del Belice (VDB) breed and the other sheep breeds considered as ancestors, using -lactoglobulin (BLG) promoter region polymorphisms. The BLG promoter region of 50 randomly chosen animals from the four breeds (VDB n=20; Comisana (COM) n=10; Pinzirita (PIN) n=10; Sarda (SAR) n=10) were sequenced and aligned, and results showed the presence of 36 single nucleotide polymorphisms (SNPs) and one deletion. The number of polymorphic sites identified showed high variability within breeds. Nucleotide (π) and haplotype (Hd) diversity were estimated with DnaSP software, whereas PHASE software w…
The Sicilian cattle breeds in a global context: genome-wide relationship with other worldwide cattle
2015
Genomic technologies, such as high-throughput genotyping based on Single Nucleotide Polymorphism (SNP) arrays, provide background information concerning genome structure in domestic animals. The aims of this study were to cluster animals, to explore the relationships among and within breeds, and to place the Sicilian breeds, Cinisara and Modicana, in a global context. The Illumina Bovine SNP50K v2 BeadChip genotyping data from 144 animals of Sicilian breeds and from other 1,543 animals belonging to 134 domesticated bovid breeds (DRYAD) were used. These breeds arose from 3 domesticated (sub)species: Bos javanicus, B. taurus indicus, and B. t. taurus. Principal Component Analysis (PCA) genera…
Casein haplotype variability in Sicilian dairy goat breeds
2008
In the Mediterranean region, goat milk production is an important economic activity. In the present study, 4 casein genes were genotyped in 5 Sicilian goat breeds to 1) identify casein haplotypes present in the Argentata dell'Etna, Girgentana, Messinese, Derivata di Siria, and Maltese goat breeds; and 2) describe the structure of the Sicilian goat breeds based on casein haplotypes and allele frequencies. In a sample of 540 dairy goats, 67 different haplotypes with frequency >or=0.01 and 27 with frequency >or=0.03 were observed. The most common CSN1S1-CSN2-CSN1S2-CSN3 haplotype for Derivata di Siria and Maltese was FCFB (0.17 and 0.22, respectively), whereas for Argentata dell'Etna, Girgenta…
Survey of milk protein polymorphism in the "Rossa Siciliana" dairy cattle
2005
“Rossa Siciliana” is a dairy cattle population traditionally linked to cheese production protein polymorphisms from 62 individual milk samples from 19 farms were analyzed by isoelectrofocusing. High variability was found at the CNS1S1, CSN2, CSN3, LGB and LALBA loci, while the CNS1S2 locus was monomorphic for the A allele. The casein haplotype frequencies and the occurrence of the linkage disequilibrium, taking into account the association among loci were investigated. The population was not in Hardy-Weinberg equilibrium (Chi-square=19.0, p-value=0.0407), probably due to genetic drift. Frequencies of the three allele detected at CSN1S1 locus were B (0.734), C (0.258) and D (0.008). high fre…
Application of molecular markers to investigate genetic diversity in Sicilian livestock
2014
La diversità genetica delle specie e razze di interesse zootecnico, rappresenta un’importante risorsa in tutti i sistemi di allevamento . Per lo studio della diversità genetica, nel corso dei decenni sono stati sviluppati diversi metodi che si basano su informazioni del pedigree o su dati molecolari (microsatelliti e SNPs, Single Nucleotide Polymorphisms). Con l’aumento della disponibilità di marcatori molecolari per la maggior parte delle specie di interesse zootecnico, e con lo sviluppo di sofisticate tecniche analitiche, sta crescendo la capacità di caratterizzare la variabilità genetica delle razze. Inoltre, ad oggi, poche sono le informazioni sulla diversità genetica delle razze e dell…
A genome-wide perspective on the population structure of Italian cattle breeds
2018
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…
Effects of nutritional level on lactating response of Girgentana goats with different CSN1S1 genotype
2011
Goat polymorphism at αs1-casein loci (CSN1S1) influences milk yield and composition. Milk of goats with strong alleles associated to high αs1-casein shows higher fat and casein, longer coagulation time, firmer curds and variation in fatty acids than milk from goats with weak alleles linked to low αs1-casein. Since these milk properties are also affected by nutrition, the aim of this study was to investigate the impact of nutritional level on milk production traits of Girgentana goats with different CSN1S1 genotype. From a group of goats genotyped using PRC protocols at DNA level, 12 goats having the same genotype at αs2, β and κ- casein loci and differing for CSN1S1 genotype were selected: …
Interaction between stearoyl-coenzyme A desaturase polymorphism and feeding system in affecting the fatty acid profile of sheep cheese
2021
Stearoyl-coenzyme A desaturase (SCD) catalyses the synthesis of monounsaturated fatty acids, by introducing a cis double bond at the delta 9–10 position. The study investigated the effects of a polymorphism at the ovine SCD gene and its interaction with the inclusion of fresh forage in the diet on cheese fatty acid (FA) composition in Valle del Belice ewes. A region of 527 bp of the ovine SCD gene including the partial sequence of the promoter, the complete sequence of the 5’ UTR and exon 1 and the partial sequence of intron 1 were analyzed in order to identify the g.87C > A SNP located in the promoter region. A feeding trial was carried out using 16 Valle del Belice ewes selected on the…