β-lactoglobulin gene promoter: new SNPs in sheep and goat

β-lactoglobulin (β-lg) is the major whey protein in milk of ruminants and several non ruminant species, but it is lacking in rodents, lagomorphs and human. The aim of this work was sequencing the promoter region of β-lg gene in Sicilian sheep and goat dairy breeds, in order to identify polymorphisms. In these species, the promoter region was aligned using the sequences available on database. A common set of primers was designed to amplify and sequence a fragment of approximately 2.1 kb. Within this region, 12 single nucleotide polymorphisms (SNPs) were identified in goat breeds: 7 out of them were not yet reported in literature. Moreover, in sheep breeds 15 SNPs were newly identified. Using TRANSFAC database, binding sites for transcription factors (TFs) were found within the β-lg promoter region, in sheep and goat. Multiple binding sites to MPBFs, NF-1, C/EBP, and Sp1 are present within conserved regions, both in sheep and goat. Some SNPs found in the promoter region were detected within TFs sites in both species. Further studies are required to investigate the effect of these point mutations on binding affinity of TFs, their relationship with β-lg gene expression and milk production.