The aim of this work was to sequence thepromoter region of b-lactoglobulin (BLG) gene in foursheep breeds, in order to identify polymorphisms, infer andanalyze haplotypes, and phylogenetic relationship amongthe Valle del Belice breed and the other three breedsconsidered as ancestors. Sequencing analysis and alignmentof the obtained sequences showed the presence of 36single nucleotide polymorphisms (SNPs) and one deletion.A total of 22 haplotypes found in ‘‘best’’ reconstructionwere inferred considering the 37 polymorphic sites identified.Haplotypes were used for the reconstruction of aphylogenetic tree using the Neighbor-Joining algorithm.The number of polymorphisms identified showed highvariability within breeds. Analysis of genetic diversityindexes showed that the Sarda breed presented the lowestnucleotide diversity, whereas the Comisana breed presentedthe highest one. Comparing the nucleotide diversityamong breeds, the highest value was obtained betweenValle del Belice and Pinzirita breeds, whereas the lowestone was between Valle del Belice and Sarda breeds.Considering that polymorphisms in the promoter region ofBLG gene could have a functional role associated with milkcomposition, the lowest value of nucleotide diversitybetween Valle del Belice and Sarda breeds may be related to a higher similarity of milk composition of these twobreeds compared to the others. Further analyses will beconducted in order to evaluate the possible correlationbetween the genetic diversity indexes and the BLG contentin milk of our breeds.
|Numero di pagine||7|
|Rivista||Molecular Biology Reports|
|Stato di pubblicazione||Published - 2012|
All Science Journal Classification (ASJC) codes