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Identification of genetic predispositions to susceptibility towards bovine tuberculosis (bTB) for the purpose of improving herd resistance to bTB through marker/genomic selection has been one of the thrust areas of research in animal production. Immune response genes, such as Toll Like Receptors (TLRs) which are involved in mycobacterial recognition and activation of innate and adaptive immune responses and Tumor Necrosis Factor alpha (TNFa) which is a vital pro-inflammatory cytokine with pleiotropic roles in immune response that enables mounting of a strong microbicidal action, are potential strong candidates for exploring genetic basis of resistance. Present investigation was aimed at exploring the association of three SNPs (rs43702940, rs68343175 and rs55617317) in TLR1 gene and one SNP (rs109967811) in TNFa gene with susceptibility to bTB infection in cattle. In a case-control population of bTB established using single intradermal tuberculin test, three of the investigated SNPs were found to be polymorphic while rs43702940 revealed monomorphism. SNP loci rs109967811 in TNFa gene was found to be significantly (P < 0.01) associated with susceptibility to bTB in the study population. These findings suggest that SNPs rs109967811 located in exonic region of TNFa can likely serve as a potential marker against bTB infection in cattle upon validation in independent, larger resource population. [ABSTRACT FROM AUTHOR]

Toll-like Receptor 9 (TLR9) play an important role in recognition of components of intracellular pathogens like Mycobacterium bovis and subsequent activation of both innate and adaptive immune response and is potential strong candidates for investigating genetic basis of disease resistance. Present investigation was aimed at exploring the association of four SNPs in TLR9 gene with susceptibility/resistance against bovine tuberculosis infection in cattle. Three of SNPs under investigation (rs210982793, rs207807011, rs209190268) revealed polymorphism whereas monomorphism was observed in SNP rs55617140. SNP loci rs210982793 and rs207807011 were significantly (P < 0.01) associated with susceptibility to bovine tuberculosis in the case control population. Both these SNPs loci were non-synonymous, thus suggestive of their functional role in the immune response against bovine tuberculosis. [ABSTRACT FROM AUTHOR]

The present study in the 5’ upstream region of TLR4 gene revealed four Single Nucleotide Polymorphisms (SNPs) in Vrindavani and Tharparkar cattle. The polymorphic information content (PIC), heterozygosity and allelic diversity values were low to moderate for these SNPs. In Vrindavani cattle, one SNP was found to be in Hardy-Weinberg Equilibrium (HWE) and the remaining three were found to be in linkage disequilibrium (LD) as indicated statistically (P > 0.05). In Tharparkar cattle, two SNPs were found to be in HWE and were not in LD as indicated statistically (P > 0.05). These SNPs were used for construction of haplotypes. In-silico analysis of these SNPs predicted abolition of eight transcription factor binding sites and creation of eight new sites. The quantitative real time PCR analysis did not show any significant variation of gene expression among haplotypes. However, gene expression between breed was found to be significant (P < 0.05) which suggested that upstream region of bovine TLR4 gene has a crucial role in its expression. These findings in TLR4 gene offer essential evidence that can be useful in future research exploring its role in immunity. TLR4 can be used as a marker for selection for disease resistance in bovines. [ABSTRACT FROM AUTHOR]

• Haplotype structure was elucidated in Vrindavani cattle via sliding window approach. • Haplotype-based association analysis was undertaken with (re)production traits. • Haplotypes showed significant association with AFC, TLMY, PY, DD, ICP and SP. • Overlapping candidate genes revealed pathways affecting the (re)production performance. Haplotype-based association analysis promises to reveal important information regarding the effect of genetic variants on economic traits of interest. The present study aimed to evaluate the haplotype structure of Vrindavani cattle and explore the association of haplotypes with (re)production traits of economic interest. Genotyping array data of medium density (Bovine50KSNP BeadChip) on 96 randomly selected Vrindavani cows was used in the present study. Genotypes were called in GenomeStudio program while quality control was undertaken in PLINK using standard thresholds. The phenotypic traits used in the present study included age at first calving, dry days, lactation length, peak yield, total lactation milk yield, inter-calving period and service period. The haplotype structure of Vrindavani population was assessed, using a sliding window of 20 SNP with a shift of 5 SNPs at a time, in terms of the size of haplotype blocks regarding their length (in Kb) and frequency in chromosome-wise fashion. Haplotype blocks were assessed for possible association with important production and reproduction traits across three lactation cycles in Vrindavani cattle population. The first ten principal components were included in the model for haplotype-based association analysis to correct for stratification effects of assessed individuals. Multiple haplotypes were found to be associated with age at first calving, total lactation milk yield, peak yield, dry days, inter-calving period and service period. Various candidate genes were found to overlap haplotypes that were significantly associated with age at first calving (CDH18, MARCHF11, MYO10, FBXL7), total lactation milk yield (TGF, PDE1A, and COL8A1), peak yield (PPARGC1A, RCAN1, KCNE1, SMIM34 and MRPS6), dry days (CPNE4, ACAD11 and MRAS), inter-calving period (ABCG5, ABCG8 and COX7A2L) and service period (FOXL2 and PIK3CB). The putative candidate genes overlapping the significantly associated haplotypes revealed important pathways affecting the production and reproduction performance of animals. The identified genes and pathways may serve as good candidate markers to select animals for improved production and reproduction performance in future generations. [ABSTRACT FROM AUTHOR]