Association between CRP gene polymorphisms and the risk of preeclampsia in Han Chinese women

Genetic variant rs1205 is associated with COVID-19 outcomes: The Strong Heart Study and Strong Heart Family Study

BACKGROUND

Although COVID-19 infection has been associated with a number of clinical and environmental risk factors, host genetic variation has also been associated with the incidence and morbidity of infection. The CRP gene codes for a critical component of the innate immune system and CRP variants have been reported associated with infectious disease and vaccination outcomes. We investigated possible associations between COVID-19 outcome and a limited number of candidate gene variants including rs1205.

METHODOLOGY/PRINCIPAL FINDINGS

The Strong Heart and Strong Heart Family studies have accumulated detailed genetic, cardiovascular risk and event data in geographically dispersed American Indian communities since 1988. Genotypic data and 91 COVID-19 adjudicated deaths or hospitalizations from 2/1/20 through 3/1/23 were identified among 3,780 participants in two subsets. Among 21 candidate variants including genes in the interferon response pathway, APOE, TMPRSS2, TLR3, the HLA complex and the ABO blood group, only rs1205, a 3' untranslated region variant in the CRP gene, showed nominally significant association in T-dominant model analyses (odds ratio 1.859, 95%CI 1.001-3.453, p = 0.049) after adjustment for age, sex, center, body mass index, and a history of cardiovascular disease. Within the younger subset, association with the rs1205 T-Dom genotype was stronger, both in the same adjusted logistic model and in the SOLAR analysis also adjusting for other genetic relatedness.

CONCLUSION

A T-dominant genotype of rs1205 in the CRP gene is associated with COVID-19 death or hospitalization, even after adjustment for relevant clinical factors and potential participant relatedness. Additional study of other populations and genetic variants of this gene are warranted.

The death rate of COVID-19 infection in different SARS-CoV-2 variants was related to C-reactive protein gene polymorphisms

The serum level of C-reactive protein (CRP) is a significant independent risk factor for Coronavirus disease 2019 (COVID-19). A link was found between serum CRP and genetic diversity within the CRP gene in earlier research. This study examined whether CRP rs1205 and rs1800947 polymorphisms were associated with COVID-19 mortality among various severe acute respiratory syndrome Coronavirus 2 (SARS-CoV-2) variants. We genotyped CRP rs1205 and rs1800947 polymorphisms in 2023 deceased and 2307 recovered patients using the polymerase chain reaction-restriction fragment length polymorphism method. There was a significant difference between the recovered and the deceased patients in terms of the minor allele frequency of CRP rs1205 T and rs1800947 G. In all three variants, COVID-19 mortality rates were associated with CRP rs1800947 GG genotype. Furthermore, CRP rs1205 CC and rs1800947 GG genotypes showed higher CRP levels. It was found that the G-T haplotype was prevalent in all SARS-CoV-2 variants. The C-C and C-T haplotypes were statistically significant in Delta and Omicron BA.5 variants, respectively. In conclusion, polymorphisms within the CRP gene may relate to serum CRP levels and mortality among COVID-19 patients. In order to verify the utility of CRP polymorphism correlation in predicting COVID-19 mortality, a replication of these results is needed.

Unactivated leukocyte expression of C-reactive protein is minimal and not dependent on rs1205 genotype

C-reactive protein (CRP), a prominent component of the innate immune system, is implicated in the pathophysiology of many conditions. CRP production primarily occurs in the liver; but contributions from other tissues is unclear. The Genotype-Tissue Expression Portal shows essentially no expression in whole blood and reports in the literature are conflicting. Multiple genomic variants influence serum levels of CRP. We measured CRP mRNA expression in leukocytes and sought to determine if rs1205 genotype influences leukocyte expression. Leukocytes were obtained from 20 women differing by genotype. Quantitative, real-time PCR (RT-qPCR) detected CRP and reference gene (GAPDH) mRNA. Leukocyte expression was calculated by the 2^ΔCT method, and against a standard curve. Digital drop PCR was also used to calculate expression ratios. Student's t test and linear regression methods examined possible differences between genotypes. During 32 runs (10 replicates each), the RT-qPCR mean (SD) CRP/GAPDH ratio was 3.39 × 10^–4 (SD 1.73 × 10^–4) and 3.15 × 10^–4 (SD 1.64 × 10^–4) for TT and CC genotypes respectively, p = 0.76; and digital drop PCR results were similar. Serum CRP was not significantly different between genotypes, nor correlated with leukocyte expression. CRP is minimally expressed in unactivated leukocytes and this expression is not likely influenced by rs1205 genotype.

Accuracy of Soluble Endoglin for Diagnosis of Preeclampsia and its Severity

Background

The use of biomarkers for diagnosis of Preeclampsia (PE), a life-threatening pregnancy disorder, could reduce serious complications of this disease. In this study, we investigated dysregulation of endoglin (Eng) expression and diagnostic accuracy of soluble endoglin (sEng) in PE patients.

Methods

For this case-control study, 26 mild and 15 severe preeclamptic women along with 20 normotensive controls were recruited. The expression level of Eng (the co-receptor of TGF-β1) was evaluated using qRT-PCR. Also, the serum concentration of soluble Eng and expression of membranous Eng were determined by ELISA and immunohistochemistry.

Results

A significant up-regulation in Eng mRNA and sEng levels was observed in PE patients versus normal controls. Immunohistochemistry (IHC) showed up-regulation of membranous Eng staining in syncytiotrophoblast and cytotrophoblast cells of PE patients. The serum levels of sEng were significantly increased in all patients (mild, sever, early- and late-onset) as compared to healthy pregnant women (P˂0.001). Receiver-operating characteristic (ROC) curve analysis revealed that sEng had the highest accuracy in distinguishing PE from normal pregnancies with cut-off value of 20.4, sensitivity of 92.1%, specificity of 90%, and area under the curve (AUC) of 0.94 (95% CI: 0.88-1.00).

Conclusion

Our data showed that the up-regulation of Eng mRNA along with its membranous and soluble form in PE patients leads to defect in angiogenesis pathway. Also, the results of this study revealed sEng potential as a marker for diagnosis of PE and its severity.

Contribution of TIMP3 polymorphisms to the development of preeclampsia in Han Chinese women

PURPOSE

The aim of this study was to investigate whether polymorphisms in the tissue inhibitor of metalloproteinase 3 gene (TIMP3) are associated with the risk of preeclampsia (PE) in Han Chinese women.

METHODS

Nine single TIMP3 tag-single nucleotide polymorphisms were selected by Haploview and genotyped using the Sequenom method in 181 preeclamptic and 203 healthy pregnant women from eastern China.

RESULTS

The allele frequencies of the tag-single nucleotide polymorphisms were not significantly different between groups (P > 0.05). However, the genotype distribution of rs135025 was shown to differ between the multigravidity PE subgroup (>3) and controls under additive (P = 0.018) and recessive models (P = 0.008), while the genotype distribution of rs80272 differed significantly between the severe PE subgroup and controls under additive (P = 0.014) and dominant models (P = 0.041). Moreover, the H2 haplotype (A-C-G-T-A-A-G-C-G) was found to be associated with the risk of PE (P = 0.035).

CONCLUSIONS

Genotypes of rs135025 and rs80272 in TIMP3 may therefore influence susceptibility to PE, and pregnant women carrying the H2 haplotype might be more prone to developing PE.