Influence of methylmalonyl‐CoA mutase alleles on resistance to bovine tuberculosis in the European wild boar (Sus scrofa)

Abstract

An association study was carried out to examine the influence of methylmalonyl-CoA mutase (MUT) polymorphisms on the susceptibility of a well-studied wild boar population from southern Spain to develop bovine tuberculosis (bTB). To this end, we examined polymorphisms at a closely linked dinucleotide microsatellite flanking exon 2 of the MUT gene in 37 wild boars with bTB and 36 non-infected individuals. The microsatellite showed low polymorphism in the studied population, with only three alleles (MUTm-A, MUTm-B and MUTm-C) found, in contrast to the 11 alleles previously reported for domestic pigs. Our case-control study showed that the MUTm-B allele was associated with disease in a dominant pattern (odds ratio = 3.36; 95% CI = 1.05-10.72; P = 0.04), while the MUTm AA genotype appeared to have a protective effect against bTB infection (odds ratio = 4.33; 95% CI = 1.20-14.96; P = 0.02). Interestingly, infected wild boars heterozygous for MUTm AB are at an advantage (11-fold) to contain the systemic spread of the disease when compared to other genotypes, implying that a balanced polymorphism may be present in the population. These results strengthen previous observations regarding the importance of the MUT gene on bTB resistance in wild boars and indicate that polymorphisms at this locus will influence the risk of acquiring and maintaining bTB in the studied population.

Oral Vaccination with Heat Inactivated Mycobacterium bovis Activates the Complement System to Protect against Tuberculosis

“…Comparison of control animals with high (40–53; N = 3) and low (15–23; N = 5) tuberculous lesion score (Fig. 1A), showed that as in previous experiments with natural wild boar populations [13]–[15], [40], C3 and MUT mRNA levels were higher in less tuberculous animals at T1 (Fig. 3B).…”

Protection against Tuberculosis in Eurasian Wild Boar Vaccinated with Heat-Inactivated Mycobacterium bovis

“…Some of these genes such as C3 and MUT were shown to correlate with resistance to natural M. bovis infection and protection against M. bovis challenge in BCG-vaccinated wild boar [6], [17], [21]–[22]. As in previous experiments [17], [21]–[23], [50], MUT mRNA levels increased with BCG vaccination and decreased after M. bovis infection.…”

“…M. bovis infection affects gene expression in wild boar [22]–[23], [48]–[50]. Some of these genes such as C3 and MUT were shown to correlate with resistance to natural M. bovis infection and protection against M. bovis challenge in BCG-vaccinated wild boar [6], [17], [21]–[22].…”

“…The immunoregulatory genes, complement component 3 (C3) and methylmalonyl-CoA mutase (MUT) were selected for analysis based on their association with wild boar resistance to natural M. bovis infection and protection against M. bovis challenge in BCG-vaccinated wild boar [6], [17], [21]–[22].…”

Fine-tuning the space, time, and host distribution of mycobacteria in wildlife

“…The relevance of these findings is that they demonstrate that M. bovis infected wildlife hosts may become infected more than once under natural conditions, at least in areas of high infection pressure such as DNP. These results also suggest that cross-protection between different M. bovis strains is limited, further underlining the importance of genetic factors rather than immune responses in controlling mycobacterial infections in wildlife [11,47,48]. Additionally, the infection exclusion reported for closely related genotypes of other intracellular bacteria of the genus Anaplasma [49] did not appear to occur for M. bovis TPs.…”