Simple genotype analysis of the Asp299Gly polymorphism of the Toll‐like receptor‐4 gene that is associated with lipopolysaccharide hyporesponsiveness

Abstract

A nonsynonymous single nucleotide polymorphism (Asp299Gly) in the Toll-like receptor-4 (TLR-4) gene affects the responsiveness to lipopolysaccharide in humans. To analyze this important polymorphism more efficiently, we developed a simple polymerase chain reaction (PCR) restriction length fragment polymorphism (RFLP) assay and examined the Asp299Gly allele frequency in a Japanese population. The PCR primer was designed with 1- or 2-bp mismatches, creating the recognition sequence for restriction enzyme BsaBI or BstXI, allowing RFLP analysis of the digested products. Genotyping was carried out with this assay for 275 DNA specimens from 107 healthy volunteers and 168 patients with various diseases, including ulcerative colitis (n = 86). The Asp299Gly allele of the TLR-4 gene was not detected in any of the specimens, suggesting that it is very rare in Japanese.

Genetic polymorphisms in TLR4, CR1 and Duffy genes are not associated with malaria resistance in patients from Baixo Amazonas region, Brazil

“…The Asp299Gly polymorphism determination in the TLR4 (A896G) genes followed the protocol suggested by Okayama et al (2002). The determination of the Gly42Asp (G125A), Arg89Cys (C265T), Ala100Thr (G298A) polymorphisms of the Duffy gene (FY) coding region followed the protocol suggested by Parasol et al (1998), and the T33C polymorphism determination of the Duffy gene (FY) promoter region (GATA-1 box) followed the protocol suggested by Yazdanbakhsh et al (2000).…”

TLR4 inactivation protects from graft-versus-host disease after allogeneic hematopoietic stem cell transplantation

“…[15][16][17][18][19] The TLR4 Asp299Gly polymorphism, in particular, is the highest in African Americans, while in a western Iran population, the highest incidence for a mutation was found for the TLR4 Thr399Ile polymorphism, which is in, contrast, very rare in Asian populations, such as those in Japan and South Korea. 20,21 Carriers of the Thr399Ile TLR4 gene mutation have a significantly increased risk of developing GVHD, 42% versus 15% of non-affected patients, whereas transplant-related mortality, overall survival rate and the incidence of infectious complications are not influenced by the mutated gene. 22 Histopathological changes in the small intestine are more severe in TLR4-mutant host GVHD recipients than those in TLR4-intact host GVHD recipients at 14 days after GVHD development, 23 but the studies reporting these results did not clearly demonstrate the role of TLR4 in the HSCT-related pathogenesis of GVHD.…”

Toll-like receptor 4 and NOD2/CARD15 mutations in Hungarian patients with Crohn’s disease: Phenotype-genotype correlations

“…In contrast, the expressions of TLR2 and TLR5 are unchanged, while TLR3 is down-regulated [25] . The D299G (Asp299Gly) polymorphism of TLR4 gene is associated with LPS hyporesponsiveness [26] and recently an association between TLR4 mutation and CD was reported in one study [27] , but not in another [28] . In view of the limited data on the prevalence of NOD2/CARD15 mutations in Eastern European countries, our aim was to investigate the presence of the common three and other exon4 variants of NOD2/CARD15 as well as the presence of functional D299G polymorphism of the TLR4 gene in three large cohorts of Hungarian patients with CD.…”