Detection of polymorphism in the promoter region of TNF-alpha gene of water buffalo (Bubalus bubalis) and its association with disease resistance

Abstract

Tumour necrosis factor (TNF), a proinflammatory cytokine, plays an important role in the regulation of cell differentiation, proliferation and death, as well as in innate and adaptive immune response. In this study we have sequence characterized upstream regulatory region of TNF-á gene of buffalo. Ten single polymorphic nucleotides (SNPs) -541A/T, -553A/G, -563,C/G, -619A/G, -659A/G, -706C/G, -730G/T, -794A/G, -898G/T, -981A/G) along with one indel at position -783 were identified. Further when analysed, among riverine and swamp types, 16 and 17 transcription factor–binding sites (TFBS) respectively were observed. Riverine and swamp buffaloes differed by PAX-2 transcription factor binding site at position -541 present in riverine and absent in swamp, important in the proliferation of multiple cell lines and development of organs. Comparative analysis of TNF-á upstream region revealed presence of additional NF-k binding site in buffalo and v-Myb binding site in cattle only. Genotyping of SNP -794A/G by tetra-ARMS PCR revealed variable allele frequencies among riverine and swamp buffaloes, however in clinical mastitis affected and non-affected Murrah buffaloes this SNP didn’t show any significant association with mastitis resistance. Overall study reveals the sequence variation in TNF-á promoter, possibly leading to modification of transcriptional regulation in swamp and riverine buffalo.