PLA2G2A polymorphisms are associated with metabolic syndrome and type 2 diabetes mellitus. Results from the genetics of atherosclerotic disease Mexican study

The secretory phospholipase A₂ II A (sPLA₂-IIA) encoded by PLA2G2A gene hydrolyzes phospholipids liberating free fatty acids (FFAs) and lysophospholipids. If lipolysis exceeds lipogenesis, the free fatty acids undergo a continuous release into circulation. A sustained excessive increase in this release contributes to metabolic disease. The aim of the present study was to evaluate the role of PLA2G2A gene polymorphisms as susceptibility markers for metabolic syndrome (MetS) and type 2 diabetes mellitus (T2DM) in Mexican population. Three PLA2G2A gene polymorphisms (rs876018, rs3753827 and rs11573156) were genotyped by 5′ exonuclease TaqMan assays in a group of 338 patients with T2DM, 460 individuals with MetS and 366 healthy controls. Under codominant 1 (codom1), dominant (dom) and additive (add) models adjusted by age, gender, body mass index (BMI), smoking habit, and hypertension, the rs876018 T allele was associated with increased risk of MetS [Odds Ratio (OR) = 1.66, P_codom1 = 0.005; OR = 1.67, P_dom = 0.003; OR = 1.49, P_add = 0.005] as compared to controls. On the other hand, under several models adjusted by the same variables, the rs3753827 A (OR = 1.52, P_codom1 = 0.039 and OR = 1.49, P_dom = 0.039) and rs11573156C alleles (OR = 6.46, P_codom1 = 0.013; OR = 6.70, P_codom2 = 0.009; OR = 6.65, P_dom = 0.009) were associated with increased risk of T2DM when compared with controls. In addition, the rs876018 T allele was associated with hypercholesterolemia (P_dom = 0.017, P_add = 0.009) and risk of subclinical atherosclerosis (SA) (P_dom = 0.041) in MetS when compared with controls. Also, this allele was associated with SA in T2DM patients (P_dom = 0.007). The TAG haplotype was significantly associated with increased risk of MetS (OR = 1.54, P = 0.006). Results suggest that PLA2G2A polymorphisms are involved in the risk of developing MetS and T2D and are associated with SA in this group of patients.     

Association of rs1285933 single nucleotide polymorphism in CLEC5A gene with dengue severity and its functional effects

Outbreaks of the Zika, dengue, and chikungunya viruses, especially in the Americas, pose a global threat due to their rapid spread and difficulty controlling the vector. Extreme phenotypes are often observed, from asymptomatic to severe clinical manifestations, which are well-studied in dengue. Host variations are also important contributors to disease outcomes, and many case-control studies have associated single nucleotide polymorphisms (SNPs) with severe dengue. Here, we found that the TC genotype and T-carriers for SNP rs1285933 in the C-type lectin superfamily member 5 (CLEC5A) gene was associated with severe dengue in a Northern Brazilian population (OR = 2.75 and p-value = 0.01, OR = 2.11 and p-value = 0.04, respectively). We also tested the functional effect of the CLEC5A protein and found that it is upregulated on the surface of human monocytes after in vitro dengue infection. CLEC5A was correlated with viral load inside the monocytes (Spearman r = 0.55, p = 0.008) and TNF production in culture supernatants (Spearman r = 0.72, p = 0.03). Analysis of mRNA in blood samples from DENV4-infected patients exhibiting mild symptoms showed that CLEC5A mRNA expression is correlated with TNF (r = 0.67, p = 0.0001) and other immune mediators. Monocytes from rs1285933 TT/TC individuals showed lower CLEC5A expression compared to CC genotypes. However, in these cells, CLEC5A was not correlated with TNF production. In summary, we confirmed that CLEC5A is genetically associated with dengue severity outcome, playing a central role during the immune response triggered by a dengue viral infection, and rs1285933 is a relevant SNP that is able to regulate signaling pathways after interactions between the dengue virus and CLEC5A receptors.     

Single-nucleotide polymorphism rs 175080 in the MLH3 gene and its relation to male infertility

PurposeMLH3, a MutL homolog protein in mammals playing a role in DNA mismatch repair, is associated with spermatogenesis and male infertility. The purpose of the present study was to investigate the association of the single-nucleotide polymorphism (SNP), rs 175080 in the MLH3 gene, with sperm parameters in a Greek population.MethodsThe study included 300 men of couples undergoing in vitro fertilization/intracytoplasmic sperm injection-embryo transfer (IVF/ICSI-ET) treatments (years 2011–2013). Genomic DNA was extracted from 300 peripheral blood samples, and conventional quantitative real-time PCR was performed for genotyping. Of them, 122 were from men used as “controls” and 178 from men used as “cases.” Allocation to the two groups was based on sperm concentrations (≥15 and <15 million/ml, respectively). Serum FSH, LH, estradiol, testosterone, and prolactin concentrations as well as sperm parameters were compared between three genotypes (GG, GA, and AA). Furthermore, the frequencies of these three genotypes were compared between “cases” and “controls.”ResultsAnthropometric parameters and hormonal values did not differ significantly between the three genotypes. Significantly lower sperm concentrations were found in men with the AA genotype as compared to men with the GG and GA genotypes (p < 0.001). The AA genotype had the lower progressive motility values as compared to the other two genotypes (p < 0.05). Also, there was a significantly different distribution of the frequencies of the three genotypes between “cases” and “controls” (p < 0.001).ConclusionsIt is suggested that the studied SNP in the MLH3 gene may be linked to oligozoospermia in Caucasian men of a certain area.     

LH (Trp8Arg/Ile15Thr), LHR (insLQ) and FSHR (Asn680Ser) polymorphisms genotypic prevalence in women with endometriosis and infertility

Purpose

To verify if polymorphisms of LH (Trp8Arg/Ile15Thr), LH receptor (insLQ), and FSH receptor (Asn680Ser) are associated with endometriosis and infertility.

Methods

This is a prospective case–control study. Sixty-seven patients with endometriosis and infertility (study group) and 65 healthy fertile patients (control group) were enrolled in the study between July 2010 and July 2013. All patients had their endometriosis diagnosis made or excluded by laparoscopic surgery; study group was submitted to the surgery for infertility investigation and control group for tubal ligation. Day-3 serum hormones were collected from all patients. Analysis of nucleotide mutations for LH polymorphisms (Trp8Arg and Ile15Thr), LHR polymorphism (insLQ), and FSHR polymorphism (Asn680Ser) were performed by PCR.

Results

Day-3 FSH, estradiol and LH serum levels were not different between the groups, while CA-125 was higher in patients with endometriosis and infertility. All polymorphisms studied were in Hardy-Weinberg equilibrium. The prevalence of insLQ was significantly higher in patients with endometriosis and infertility (P = 0.005). Allele occurrence in control group was 0.10 versus 0.25 in infertile endometriosis group (P = 0.001). There was no difference regarding Trp8Arg/Ile15Thr (P > 0.05) and Asn680Ser (P > 0.05) prevalence between groups.

Conclusion

This is the first time that prevalence of insLQ was shown to be higher in patients with endometriosis and infertility than in healthy fertile patients. There was no difference in LH and FSHR polymorphisms’ prevalence between groups.

Electronic supplementary material

The online version of this article (doi:10.1007/s10815-015-0477-3) contains supplementary material, which is available to authorized users.     

克罗恩病CARD15/NOD2基因突变的研究

目的 发现与中国人克罗恩病（CD）发病相关的单核苷酸多态性（SNP）及其与临床特点的关系.方法 临床资料完整的CD、溃疡性结肠炎（UC）患者及健康体检者各30例.提取人血白细胞基因组DNA,PCR扩增NOD2基因第4、8、11外显子,纯化后直接测序.结果 5例CD患者有SNP改变,其中2例为P268S,1例为R459R,2例为P268S和R459R,而在UC患者和健康人中各检测到1例R459R.所有研究对象未发现R702W、G908R及3020insC改变.CD有4例P268S,与UC和健康体检者比较差异有统计学意义（χ^2=8.037,P＜0.05）.4例P268S CD患者病变均在回肠（χ^2=9.231,P=0.01）,发病年龄小于20岁（χ^2=10.769,P＜0.01）,并发肠腔狭窄而需手术（χ^2=7.972,P＜0.01）,2例有P268S和R459R的患者病情较重,多次复发.结论 P268S可能是CARD15/NOD2基因中与中国人CD相关的SNP,与患者发病年龄、病变部位及肠腔狭窄明显相关,与患者性别及病变严重程度无关.     

白细胞介素-6基因-572C/G多态性与冠心病的关系及对血清IL-6水平的影响

目的:了解白细胞介素-6(IL-6)基因-572C/G多态性对冠心病(CHD)发病易感性及血清IL-6水平的影响。方法:应用聚合酶链反应-限制性片段长度多态性分析方法,测定245例CHD患者(CHD组)和260例正常对照者(对照组)的IL-6基因-572C/G多态性,探讨其与CHD的相关关系;并应用酶联免疫吸附试验法检测研究人群血清IL-6水平,观察基因型对血清IL-6水平的影响。结果:IL-6基因-572C/G基因型和等位基因频率在2组间分布差异有统计学意义,CHD组GG基因型和G等位基因频率均显著高于对照组(P<0.01);相对于CC基因型,暴露于CG、GG基因型的相对危险度分别为1.46(95%CI:1.01~2.10,P<0.05)和5.19(95%CI:1.69~15.89,P<0.01);不同基因型患者间血清IL-6水平差异无统计学意义(P>0.05)。结论:IL-6基因-572C/G多态性可能是中国汉族人群CHD发病的遗传危险因素之一,但该多态性对血清IL-6水平无影响。     

Genetic polymorphisms and surface expression of CTLA-4 and PD-1 on T cells of silica-exposed workers

Exposure to silica dust has been examined as a possible risk factor for autoimmune diseases, including scleroderma, rheumatoid arthritis and systemic lupus erythematosus. Since CTLA-4 [CD152] and PD-1 [CD279] are important for the maintenance of peripheral tolerance by regulating T cell responsiveness, we evaluated the expression of these molecules on the surface of CD4 and CD8 T cells, as well as single nucleotide polymorphisms (SNP) in CTLA-4 and PDCD1 genes, of 70 silica-exposed workers and 30 non-exposed, age-, ethnically- and sex-matched controls. Expression of CTLA-4 was significantly (P<0.05) reduced in CD4 T cells of exposed individuals [median=0.1% and interquartile range, IQR 0.0-0.1% (exposed), median=0.20%, IQR 0.0-0.4% (control)]. Also the expression of PD-1 was significantly (P<0.0001) reduced in both CD4 [median=0.9%, IQR 0.4-2.3% (exposed), median=5.7%, IQR 1.4-13.3% (control)] and CD8 T cells [median=0.9%, IQR 0.3-1.9% (exposed), median=5.0%, IQR 3.4-8.9% (control)]. The study of polymorphisms demonstrated a lower frequency of the A allele in the analysis of the PD1.3 SNP in the exposed group, which might be associated with the lower expression of PD-1 on the surface of CD4 T cells. Our findings provide evidence for the association of silica exposure and the maintenance of self-tolerance, i.e., the susceptibility to autoimmune disorders.     

Y染色体DYS287位点在白裤瑶族群体中的检测分析

目的调查广西白裤瑶族群体中DYS287基因位点的遗传多态性分布。方法采用聚合酶链反应结合琼脂糖凝胶电泳检测方法对132例白裤瑶族、149例壮族、172例汉族样本DYS287位点多态性进行检测分析。结果 132例白裤瑶族、149例壮族和172例汉族男性个体检测结果均为YAP-,未检出YAP+扩增产物。结论获得广西白裤瑶族DYS287基因座的遗传学多态性数据,为不同地域不同瑶族群体遗传关系的分析、法医鉴定及不同地域瑶族群体之间的起源关系差异提供了一定的遗传背景资料。     

白细胞介素6基因多态性与原发性高血压的关系

目的 :探讨白细胞介素 6 (IL 6 )基因 - 5 97G/A和 - 5 72C/G多态性与湖北地区汉族人群原发性高血压 (EH)的关系。方法 :以人群为基础进行EH病例 对照研究 ,应用PCR RELP技术对 10 2例EH患者和 112例正常对照者的IL 6基因 - 5 97G/A和 - 5 72C/G多态性进行分析。结果 :湖北地区汉族人群IL 6基因 - 5 97位点仅发现有GG基因型 ,未见GA和AA基因型 ;- 5 72位点以CC和CG基因型占优势。EH组 - 5 72CG +GG基因型频率及G等位基因频率分别为 5 9%和 34% ,均显著高于对照组 (P <0 .0 1) ;相对于CC基因型 ,暴露于CG基因型、GG基因型的相对危险度分别为 2 .0 2 (95 %CI:1.15～ 3.5 7,P <0 .0 5 )和 7.12 (95 %CI:2 .18～ 2 3.2 0 ,P<0 .0 1)。EH组不同基因型间总胆固醇、三酰甘油、血糖、体重指数差异均无显著性意义 (P >0 .0 5 )。结论 :湖北地区汉族人群可能不存在IL 6基因 - 5 97G/A多态性 ,而 - 5 72位点CG +GG基因型可能是此人群EH的易感基因型