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Kawasaki disease (KD) is a pediatric vasculitis caused by an unknown trigger in genetically susceptible children. The incidence varies widely across genetically diverse populations. Several associations with HLA Class I alleles have been reported in single cohort studies. Using a genetic approach, from the nine single nucleotide variants (SNVs) associated with KD susceptibility in children of European descent, we identified SNVs near the HLA-C (rs6906846) and HLA-B genes (rs2254556) whose association was replicated in a Japanese descent cohort (rs6906846 p = 0.01, rs2254556 p = 0.005). The risk allele (A at rs6906846) was also associated with HLA-C*07:02 and HLA-C*04:01 in both US multi-ethnic and Japanese cohorts and HLA-C*12:02 only in the Japanese cohort. The risk A-allele was associated with eight non-conservative amino acid substitutions (amino acid positions); Asp or Ser (9), Arg (14), Ala (49), Ala (73), Ala (90), Arg (97), Phe or Ser (99), and Phe or Ser (116) in the HLA-C peptide binding groove that binds peptides for presentation to cytotoxic T cells (CTL). This raises the possibility of increased affinity to a "KD peptide" that contributes to the vasculitis of KD in genetically susceptible children. [ABSTRACT FROM AUTHOR]

Abstract: Aims: We previously reported the association of single nucleotide polymorphisms in the lymphotoxin alpha (LTα) gene with susceptibility to acute myocardial infarction (AMI) and increased mortality after discharge. In the present study, we investigated whether the adverse effect of LTα C804A polymorphism on mortality could be pharmacologically modified by statin treatment after AMI. Methods and results: We conducted a multicenter study that included 3486 post-AMI patients between 1998 and 2008. During a median follow-up period of 1775 days, 247 deaths were recorded. The mortality rate was significantly higher in LTα 804A allele carriers compared to non-804A allele carriers (7.9% vs. 5.7%, p = 0.011). The LTα 804A allele was significantly associated with increased mortality for post-AMI patients not receiving statins (hazard ratio [HR]: 1.48, 95% confidence interval [CI]: 1.03–2.12, p = 0.034), but not for those receiving statins (HR: 1.22, 95% CI: 0.70–2.10, p = 0.486). In-vitro experimental analyses demonstrated that the LTα 804A polymorphic protein, 26Asn-LTα3, induced monocyte-endothelial interaction and endoplasmic reticulum (ER) stress in cardiomyocytes more strongly than the LTα3 804C polymorphic protein 26Thr-LTα3. However, the effects of both LTα3 proteins were decreased and became comparable by the pretreatment of cells with pravastatin. Conclusion: LTα C804A polymorphism was associated with an increased risk of mortality for AMI patients, although this effect was masked in patients treated with statins. This finding is supported by the observed attenuation of 26Asn-LTα3-mediated monocyte-endothelial interaction and ER stress in cardiomyocytes treated with pravastatin. LTα C804A polymorphism may have potential as a novel therapeutic target for secondary prevention after AMI. [Copyright &y& Elsevier]