Abstract
Johne’s disease (JD), an enteric disease of ruminants caused by
Mycobacterium avium subspecies paratuberculosis (MAP) is
responsible for a substantial economic burden on the cattle
industry. Little is known about TLR4 involvement during
infection with MAP, although mouse studies suggest that
TLR4 may be a candidate gene for resistance to MAP
infection, and studies have shown that TLR4 expression is
upregulated in ileum, jejunum, and mesenteric lymph nodes in
sheep with JD. In earlier studies, we found associations with
single nucleotide polymorphisms (SNPs: c.-226C G and
c.2021C T) in bovine TLR4 and health related traits, such
as somatic cell score in Canadian Holsteins; SNP c.-226C G
is located in 5? untranslated region, whereas c.2021C T is
located in the third exon of the TLR4 and is non-synonymous.
In this study, we examined associations between these two
SNPs and susceptibility to JD using a case-control study
comprised of 307 MAP positive and 256 MAP negative dairy
cows. The association between MAP positive and negative
cows was examined by comparing the allelic and genotypic
frequencies using x2 test. Differences in allele frequencies of c.-
226C G and c.2021C T between the MAP positive and
negative groups were 9.5% (PB0.002) and 8.7% (PB0.0001),
respectively. The genotype distribution of SNP c.-226C G
was significantly different between MAP positive and negative
animals (PB0.009), where CC and GG individuals were more
frequent in exposed and unexposed groups, respectively. SNP
c.2021C T showed larger difference (PB0.0003) between
MAP positive and negative groups. Since we have previously
shown a functional role of c.-226C G in the regulation of
TLR4 expression, further investigation regarding the role of these SNPs in controlling the susceptibility to Johne’s disease
is warranted.
Mycobacterium avium subspecies paratuberculosis (MAP) is
responsible for a substantial economic burden on the cattle
industry. Little is known about TLR4 involvement during
infection with MAP, although mouse studies suggest that
TLR4 may be a candidate gene for resistance to MAP
infection, and studies have shown that TLR4 expression is
upregulated in ileum, jejunum, and mesenteric lymph nodes in
sheep with JD. In earlier studies, we found associations with
single nucleotide polymorphisms (SNPs: c.-226C G and
c.2021C T) in bovine TLR4 and health related traits, such
as somatic cell score in Canadian Holsteins; SNP c.-226C G
is located in 5? untranslated region, whereas c.2021C T is
located in the third exon of the TLR4 and is non-synonymous.
In this study, we examined associations between these two
SNPs and susceptibility to JD using a case-control study
comprised of 307 MAP positive and 256 MAP negative dairy
cows. The association between MAP positive and negative
cows was examined by comparing the allelic and genotypic
frequencies using x2 test. Differences in allele frequencies of c.-
226C G and c.2021C T between the MAP positive and
negative groups were 9.5% (PB0.002) and 8.7% (PB0.0001),
respectively. The genotype distribution of SNP c.-226C G
was significantly different between MAP positive and negative
animals (PB0.009), where CC and GG individuals were more
frequent in exposed and unexposed groups, respectively. SNP
c.2021C T showed larger difference (PB0.0003) between
MAP positive and negative groups. Since we have previously
shown a functional role of c.-226C G in the regulation of
TLR4 expression, further investigation regarding the role of these SNPs in controlling the susceptibility to Johne’s disease
is warranted.
| Original language | English |
|---|---|
| Pages | 166-167 |
| Number of pages | 2 |
| Publication status | Published - 2009 |
| Event | Canadian Society of Animal Science Annual Meeting - Montreal, Quebec, Canada Duration: 16 Mar 2008 → 18 Mar 2008 |
Conference
| Conference | Canadian Society of Animal Science Annual Meeting |
|---|---|
| Country/Territory | Canada |
| City | Montreal, Quebec |
| Period | 16/03/08 → 18/03/08 |