Red blood cell (RBC) alloimmunization is a serious complication of blood transfusions, challenging selection of compatible units for future transfusions. Genetic characteristics may be associated... Show moreRed blood cell (RBC) alloimmunization is a serious complication of blood transfusions, challenging selection of compatible units for future transfusions. Genetic characteristics may be associated with the risk of RBC alloimmunization and may therefore serve to identify high-risk patients. The aim of this systematic review was to summarize the available evidence on genetic risk factors for RBC alloimmunization. Electronic databases were searched up to April 2020 for studies (Search terms included transfusion, alloimmunization and genetic). A total of 2581 alloimmunized cases and 26,558 controls were derived from 24 studies. The alleles that were most frequently studied and that demonstrated significant associations in a meta-analysis with alloimmunization to the Duffya antigen were HLA-DRB1*04 (Odds Ratio 7.80 (95%CI 4.57-13.33)), HLA-DRB1*15 (OR 3.76 (95%CI 2.14-6.59)), and HLA-DRB1*03 (OR 0.12 (95%CI 0.05-0.29)). Furthermore, significant associations with anti-K formation was found for the alleles HLA-DRB1*10 (OR 2.64 (95%CI 1.41-4.95)), HLA*DRB1*11 (OR 2.11, (95% CI 1.34-3.32)), and HLA-DRB1*13 (OR 1.71 (95%CI 1.26-2.33)). Overall, the available evidence was of moderate to low quality, hampering interpretation of reported results. There is an urgent need for high quality evidence on genetic risk factors for RBC alloimmunization. Show less
Lam, S.W.; Noort, V. van der; Straaten, T. van der; Honkoop, A.H.; Peters, G.J.; Guchelaar, H.J.; E. boven 2018
Familial adenomatous polyposis (FAP) is a dominantly inherited syndrome caused by germline mutations in the APC gene and characterized by the development of multiple colorectal adenomas and a high... Show moreFamilial adenomatous polyposis (FAP) is a dominantly inherited syndrome caused by germline mutations in the APC gene and characterized by the development of multiple colorectal adenomas and a high risk of developing colorectal cancer (CRC). The severity of polyposis is correlated with the site of the APC mutation. However, there is also phenotypic variability within families with the same underlying APC mutation, suggesting that additional factors influence the severity of polyposis. Genome-wide association studies identified several single nucleotide polymorphisms (SNPs) that are associated with CRC. We assessed whether these SNPs are associated with polyp multiplicity in proven APC mutation carriers. Sixteen CRC-associated SNPs were analysed in a cohort of 419 APC germline mutation carriers from 182 families. Clinical data were retrieved from the Dutch Polyposis Registry. Allele frequencies of the SNPs were compared for patients with < 100 colorectal adenomas versus patients with aeyen100 adenomas, using generalized estimating equations with the APC genotype as a covariate. We found a trend of association of two of the tested SNPs with the aeyen100 adenoma phenotype: the C alleles of rs16892766 at 8q23.3 (OR 1.71, 95 % CI 1.05-2.76, p = 0.03, dominant model) and rs3802842 at 11q23.1 (OR 1.51, 95 % CI 1.03-2.22, p = 0.04, dominant model). We identified two risk variants that are associated with a more severe phenotype in APC mutation carriers. These risk variants may partly explain the phenotypic variability in families with the same APC gene defect. Further studies with a larger sample size are recommended to evaluate and confirm the phenotypic effect of these SNPs in FAP. Show less
In a surveillance study in Jakarta, Indonesia, 88 typhoid and 26 paratyphoid fever patients were identified by blood culture. Risk factors for transmission of typhoid fever were mainly intra... Show moreIn a surveillance study in Jakarta, Indonesia, 88 typhoid and 26 paratyphoid fever patients were identified by blood culture. Risk factors for transmission of typhoid fever were mainly intra-household factors (poor hand-washing hygiene, recent household contacts), whereas paratyphoid was mainly contracted through street food. In an additional study, street vendors observed poorer hand-washing and food-handling hygiene compared to food handlers in restaurants, and had higher bacterial loads in dishwater. Further host factor-studies in (para)typhoid patients revealed that polymorphisms in genes encoding pro-inflammatory cytokines (IFN-_, IL1A/B, IL1R1, TNFRSF1A, CASP1 and CRP) were not associated with susceptibility to typhoid fever, and might therefore at most be associated with severity of disease. An association was found of typhoid fever and a polymorphism in the PARK2/PACRG proteasome-mediated protein degradation pathway through ubiquitination, similar to infection with Mycobacterium leprae. Also an association between genotypes in the Cystic Fibrosis Transmembrane Conductance Regulator (the affected protein in Cystic Fibrosis) and susceptibility to typhoid fever was found, suggesting a decreased adherence potential of S. typhi to intestinal mucosal cells with these polymorphisms. Finally, bacterial characteristics were compared by use of AFLP and biochemical/antibiotic susceptibility profiles, showing very homogeneous S. typhi and S. paratyphi A strains circulating in the study area. Show less