The DSpace digital repository system captures, stores, indexes, preserves, and distributes digital research material. http://http://dspace.unitus.it:80 2013-05-18T06:31:47Z 2013-05-18T06:31:47Z Pariset, Lorraine Savarese, Maria Carmela Cappuccio, Irene Valentini, Alessio http://hdl.handle.net/2067/118 2011-01-25T10:07:13Z 2002-12-31T23:00:00Z

Title: Use of microsatellites for genetic variation and inbreeding Authors: Pariset, Lorraine; Savarese, Maria Carmela; Cappuccio, Irene; Valentini, Alessio Abstract: A set of 11 polymorphic microsatellites has been used to assess the distribution of genetic variability in 17 flocks of the Sarda sheep breed in the Viterbo province, located in central Italy. The suitability of samples size and number of loci analysed were tested using a bootstrap procedure. The data obtained were used to estimate the genetic diversity within and among flocks, and to test the presence of inbreeding within flocks. To study the genetic relationship among flocks, a principal component analysis based on Nei standard distances was performed. The results of genetic analysis show a significant excess of homozygotes in some of the flocks. The use of genetic data for maximum likelihood tests of assignment is investigated in order to establish suitable breeding policies. This research represents a case study for the development of mating strategies suitable for incrementing genetic variability within flocks that can be applied in other domestic species showing similar breeding problems (goat, buffalo and small populations of cattle).

2002-12-31T23:00:00Z Marchitelli, Cinzia Savarese, Maria Carmela Crisà, Alessandra Nardone, Alessandro Ajmone-Marsan, Paolo Valentini, Alessio http://hdl.handle.net/2067/144 2011-01-25T10:07:06Z 2002-12-31T23:00:00Z

Title: Double muscling in Marchigiana beef breed is caused by a stop codon in the third exon of myostatin gene Authors: Marchitelli, Cinzia; Savarese, Maria Carmela; Crisà, Alessandra; Nardone, Alessandro; Ajmone-Marsan, Paolo; Valentini, Alessio Abstract: Double muscling is a partially recessive trait present in some beef breeds. It shows a high frequency in some breeds, while in others the frequency is low, and double-muscled individuals are rare. The double muscling is caused by an allelic series of mutations that cause a loss of function of the myostatin gene (GDF8). We describe here a new mutation in the myostatin gene in Marchigiana breed, a typical beef breed of Central Italy, in which rare double-muscling individuals have been described. A PCR product of the third exon was sequenced in subjects phenotypically showing double muscling, and a C > T transversion was discovered that introduces a premature stop codon. The variant found adds to the large series of mutations present in cattle, and particularly to the only two causative of double muscling in the third exon. A PCR-RFLP test is described for the rapid and effective identification of both heterozygous and homozygous subjects. It was applied to a larger survey carried on the same and also in two other beef breeds, Chianina and Romagnola. Further individuals carrying the new variant were found in Marchigiana, but none in the other breeds. The results may be important for a better comprehension of the role of myostatin in muscular development, for commercial use and for the inference of phylogeny of this gene.

2002-12-31T23:00:00Z