Single Strand Conformation Polymorphisms and Sequence Analysis of 5'-Flanking Region of IL-1B Gene in Cattle (Bos taurus)

Interleukin-1β (IL-1β), the prototypical pro-inflammatory cytokine, is produced by macrophages following exposure to bacterial products. Its role is to act upon several cell types at the site of infection to stimulate the production of pro-inflammatory molecules that will cause increase in vascular permeability. Therefore, IL-1β regulates the initiation and development of acute inflammation that may have a role in mammary gland defense during mastitis. Single nucleotide polymorphisms (SNPs) in the 5''-flanking region of this gene can modulate IL-1β function. The aim of the present study was to discover and analyze SNPs in promoter region of IL-1B gene in cattle (Bos taurus). The 5''-flanking region of IL-1B gene was screened by single strand conformation polymorphism (SSCP) in Holstein and Iranian local cattle breeds (50 local and 50Holstein). A total of 4 distinct SSCP patterns were observed, which further revealed 5 novel SNPs upon sequence analysis in Iranian local breed. From the SNPs identified in this region, polymorphism at nucleotide position -534 was found to lie in the vicinity of potential GATA and ZNF transcription factor binding sites. The SNPs identified at -383 position was shown to be present within the putative ETS factor and also core sequence of CARE transcription factor. Two SNPs at positions -534 and -340 were found within the EBF binding site. The SNPs identified in the 5''-flanking region of IL-1B gene may serve as potential candidate genetic marker(s) for disease resistant traits in cattle.