Association of interleukin-1A insertion/deletion gene polymorphism and possible high risk factors with non-alcoholic fatty liver disease in Egyptian patients

The roles of transmembrane 6 superfamily member 2 rs58542926 polymorphism in chronic liver disease: A meta-analysis of 24,147 subjects

Background

Some genetic association studies tried to investigate potential associations of transmembrane 6 superfamily member 2 (TM6SF2) polymorphisms with chronic liver disease. However, the results of these studies were not consistent. Thus, we performed the present meta‐analysis to explore associations between TM6SF2 polymorphisms and chronic liver disease in a larger pooled population.

Methods

Systematic literature research of PubMed, Web of Science, Embase, and CNKI was performed to identify eligible studies for pooled analyses. I² statistics were employed to assess between‐study heterogeneities. If I² was greater than 50%, random‐effect models (REMs) would be used to pool the data. Otherwise, fixed‐effect models (FEMs) would be applied for synthetic analyses.

Results

Totally 28 studies were included for analyses (13,137 cases and 11,010 controls). The pooled analyses showed that rs58542926 polymorphism was significantly associated with chronic liver disease in overall population (dominant model: p < 0.0001, OR = 0.70, 95% CI = 0.64–0.76, I² = 47%; recessive model: p < 0.0001, OR = 2.94, 95% CI = 2.05–4.20, I² = 0%; over‐dominant model: p < 0.0001, OR = 1.34, 95% CI = 1.23–1.47, I² = 0%; allele model: p < 0.0001, OR = 0.68, 95% CI = 0.63–0.73, I² = 47%), and these significant findings were further confirmed in both Asians and Caucasians. Stratified analyses by type of disease revealed similar positive results in hepatocellular carcinoma (HCC), cirrhosis, alcoholic liver disease (ALD) and NAFLD (Nonalcoholic fatty liver disease), but not in chronic hepatitis B infection (CHB) and chronic hepatitis C infection (CHC).

Conclusions

These results suggested that TM6SF2 rs58542926 could be used to identify individuals at higher susceptibility to chronic liver disease, especially for HCC, cirrhosis, ALD, and NAFLD.

Genetic Determinants of Dyslipidemia in African-Based Populations: A Systematic Review

Identification of genetic/genomic factors contributing to dyslipidemia is of great interest to prevention and reduction of the onset and burden of cardiovascular diseases in Africa. This systematic review summarizes available data on genetic variants associated with dyslipidemia in populations within Africa. A PubMed and EMBASE database search was conducted to identify all studies published until June 2018 on genetic susceptibility to dyslipidemia in African-based populations, excluding familial hypercholesterolemia. All studies on genetic predispositions of dyslipidemia and respecting the preestablished inclusion criteria were included in this systematic review. Because of high heterogeneity, the data were summarized narratively. Twenty-two studies investigated mostly the targeted genetic variants. A total of 51 polymorphisms in 28 susceptibility genes to dyslipidemia have been associated with a particular trait in the African populations, and through variable effects. Most polymorphisms investigated in Northern Africa seemed to have consistent effects on increasing the level of low-density lipoprotein cholesterol (LDL-C), total cholesterol, and triglycerides in patients with diabetes, myocardial infarction, coronary artery disease, and metabolic syndrome. By contrast, only Ser447Ter and C49620T variants were associated with increased LDL-C in sub-Saharan Africa. Despite few studies available in this context in the literature, certain genetic variants were consistently associated with dyslipidemia especially in Northern Africa as highlighted in this analysis. Further data, particularly from genome-wide association studies, would help establish an African-specific reference for genetic susceptibility markers of dyslipidemia.

Functional polymorphism rs3783553 in the 3'-untranslated region of IL-1A increased the risk of ischemic stroke: A case-control study

Accumulating evidence indicates interleukin-1 (IL-1) is a critical mediator of inflammatory responses in ischemic stroke (IS). The aim of this study was to investigate whether rs3783553 in the 3'-untranslated region of IL-1A was associated with the risk of IS. In this hospital-based case-control study, we genotyped the rs3783553 using polymerase chain reaction in 316 patients with IS and 332 age, sex, and ethnicity-matched controls. Plasma level of IL-1α was measured by enzyme-linked immunosorbent assay. The relative luciferase activities were measured by the Dual Luciferase assay system. The presence of ins/ins genotype was associated with higher odds ratios (ORs) of IS compared with del/del genotype (ins/ins vs del/del: adjusted OR 1.77, 95% confidence interval [CI] 1.06-2.98; recessive model: adjusted OR 1.69, 95% CI 1.06-2.70). The higher risk of IS was also observed in allele comparison (adjusted OR 1.29, 95% CI 1.00-1.65). Multivariate logistic regression analysis showed that age, hypertension, total cholesterol, triglyceride, low-density lipoprotein, and rs3783553ins/ins genotypes were independent risk factors for IS. Plasma level of IL-1α was higher among IS patients compared with controls (P = .03). Notably, IS patients with the TTCA/TTCA genotype had a higher level of IL-1α compared with those with the del/del genotype (P = .01). Luciferase reporter assay showed that the vector containing the TTCA del allele exhibited a reduced transcriptional activity in the presence of miR-122 and miR-378. These findings indicate that IL-1A rs3783553 ins/ins genotype may increase the susceptibility to IS, possibly by interrupting the binding site of miR-122 and miR-378.