A common polymorphism in SCN5A is associated with lone atrial fibrillation

The cardiac sodium channel (SCN5A) is a target for the treatment of arrhythmias. We hypothesized that vulnerability to atrial fibrillation (AF) could be caused by genetic variation in SCN5A. We recruited 157 patients with early-onset AF who lacked traditional risk factors, and 314 matched controls. SCN5A was subject to targeted genotyping of a common loss-of-function H558R polymorphism and comprehensive mutation scanning. Genotype frequencies in the AF cohort vs controls were as follows: HH, 50 vs 63%; HR, 40 vs 33%; and RR, 10 vs 4% (P=0.008). Additional coding sequence mutations were ruled out. The R558 allele was more common in patients than in controls (30 vs 21%, P=0.002), conferring an odds ratios for AF of 1.6 (95% confidence interval 1.2-2.2). The SCN5A R558 allele, present in one-third of the population, thus constitutes a risk factor for lone AF and may increase susceptibility to sodium channel blocker-induced proarrhythmia.     

A single nucleotide polymorphism in LRP2 is associated with susceptibility to Alzheimer's disease in the Chinese population

BackgroundLRP2 (also called megalin) plays a potential key role in the pathogenesis of Alzheimer's disease (AD). Recently, one genome-wide association study has revealed that the rs3755166 (G/A) polymorphism located in the LRP2 promoter is associated with development of AD in Caucasians, while there are no studies on the association LRP2 of with AD risk in Asians.MethodsTo evaluate the relationship between the rs3755166 polymorphism of the LRP2 gene and AD in the ethnic Chinese Han, we conducted a case-control study (n = 361, age > 50) to determine the prevalence of one common single-nucleotide polymorphism (SNP) of LRP2 (rs3755166) in patients with AD in Chinese population of Mainland China, and clarified whether this polymorphism is a risk factor for AD.ResultsThe prevalence of the minor allele (A) in the rs3755166 polymorphism was significantly different in AD patients and control subjects (P < 0.05). The rs3755166 polymorphism was associated with AD in the ethnic Chinese Han (OR = 1.378, 95% CI: 1.017-1.867, P = 0.039), and the results were not influenced by age, gender, or APOE status (P = 0.441, P = 0.94, P = 0.432, respectively).ConclusionOur data revealed the allele (A) of the rs3755166 polymorphism within LRP2 gene may contribute to AD risk in the Chinese Han Population.     

HER2 codon 655 polymorphism is associated with advanced uterine cervical carcinoma

Objectives:It has been suggested that overexpression of HER2 in advanced cervical tumors can be considered an independent predictor of poor patient outcome.Design and methods:Employing PCR-RFLPs, we examined the distribution of HER2 Ile655Val (rs 1136201) genotypes and alleles in patients with advanced cervical cancer (n = 109) and controls (n = 220).Results:Odds ratio (OR) for patients with advanced cervical cancer with the HER2 Val/Val homozygous or Val/Ile heterozygous state was 1.778 (95% CI = 1.117–2.830, p = 0.0176). We also observed an association of the HER2 Val/Val genotype with advanced cervical cancer in the patient group OR = 3.706 (95% CI = 1.061–12.950, p = 0.0459). However, we did not find a significant association between the distribution of genotypes or alleles and cancer characteristics for the HER2 Ile655Val polymorphism.Conclusions:Our results indicate that the HER2 655Val variant may be associated with the incidence of advanced cervical cancer.     

A polymorphism in TIM1 is associated with susceptibility to severe hepatitis A virus infection in humans

During infection with the hepatitis A virus (HAV), most patients develop mild or asymptomatic disease. However, a small number of patients develop serious, life-threatening hepatitis. We investigated this variability in disease severity by examining 30 Argentinean patients with HAV-induced acute liver failure in a case-control, cross-sectional, observational study. We found that HAV-induced severe liver disease was associated with a 6-amino-acid insertion in TIM1/HAVCR1 (157insMTTTVP), the gene encoding the HAV receptor. This polymorphism was previously shown to be associated with protection against asthma and allergic diseases and with HIV progression. In binding assays, the TIM-1 protein containing the 157insMTTTVP insertion polymorphism bound HAV more efficiently. When expressed by human natural killer T (NKT) cells, this long form resulted in greater NKT cell cytolytic activity against HAV-infected liver cells, compared with the shorter TIM-1 protein without the polymorphism. To our knowledge, the 157insMTTTVP polymorphism in TIM1 is the first genetic susceptibility factor shown to predispose to HAV-induced acute liver failure. Furthermore, these results suggest that HAV infection has driven the natural selection of shorter forms of the TIM-1 protein, which binds HAV less efficiently, thereby protecting against severe HAV-induced disease, but which may predispose toward inflammation associated with asthma and allergy.     

Interleukin‐18 gene 105A/C genetic polymorphism is associated with the susceptibility of Kawasaki disease

Interleukin‐18 (IL‐18)‐656T/G, ‐607A/C, and ‐137C/G promoter polymorphisms had been reported associated with Kawasaki disease (KD). An IL‐18 genetic A/C polymorphism at coding position 105 (rs549908) has been linked with asthma, rheumatoid, and systemic lupus erythematosus. We tested a hypothesis that the IL‐18 105A/C genetic polymorphism confers KD susceptibility. Study participants were Taiwanese KD patients and a healthy control group. Our data indicated that the frequency of C allele was significantly higher in the patient group (13.9%) than in the control group (2.7%; P<0.0001, odds ratio [OR]=5.93; 95% confidence interval [CI]=2.57–13.73). Therefore, persons with the C allele may have higher risk of deve loping KD. In addition, compared with the haplotype frequencies between case and control groups, the KD patients with TACC haplotype appeared to be a significant “at‐risk” haplotype compared with other haplotypes (OR: 4.62, 95% CI: 1.71–12.43; P=0.001). KD patient with the TAGA haplotype appeared to be a significant “protective” haplotype compared with other haplotypes (OR: 0.51, 95% CI:0.29–0.89; P=0.017). Our results suggest that 105A/C polymorphism and the haplotypes in IL‐18 gene are associated with the risk of KD in Taiwanese population. Clin. Lab. Anal. 23:71–76, 2009. © 2009 Wiley‐Liss, Inc.     

A functional promoter polymorphism in monocyte chemoattractant protein-1 is associated with increased susceptibility to pulmonary tuberculosis

We examined the distribution of single nucleotide polymorphisms (SNPs) in nitric oxide synthase 2A, monocyte chemoattractant protein-1 (MCP-1), regulated on activation, normal T cell expressed and secreted, and macrophage inflammatory protein-1alpha genes in tuberculosis patients and healthy controls from Mexico. The odds of developing tuberculosis were 2.3- and 5.4-fold higher in carriers of MCP-1 genotypes AG and GG than in homozygous AA. Cases of homozygous GG had the highest plasma levels of MCP-1 and the lowest plasma levels of IL-12p40, and these values were negatively correlated. Furthermore, stimulation of monocytes from healthy carriers of the genotype GG with Mycobacterium tuberculosis antigens yielded higher MCP-1 and lower IL-12p40 concentrations than parallel experiments with monocytes from homozygous AA. Addition of anti-MCP-1 increased IL-12p40 levels in cultures of M. tuberculosis-stimulated monocytes from homozygous GG, and addition of exogenous MCP-1 reduced IL-12p40 production by M. tuberculosis-stimulated monocytes from homozygous AA. Furthermore, we could replicate our results in Korean subjects, in whom the odds of developing tuberculosis were 2.8- and 6.9-fold higher in carriers of MCP-1 genotypes AG and GG than in homozygous AA. Our findings suggest that persons bearing the MCP-1 genotype GG produce high concentrations of MCP-1, which inhibits production of IL-12p40 in response to M. tuberculosis and increases the likelihood that M. tuberculosis infection will progress to active pulmonary tuberculosis.     

HER2 Ile655Val polymorphism is negatively associated with breast cancer susceptibility

Background

The HER2 (human epidermal growth factor receptor‐2) Ile655Val (rs1136201) genetic polymorphism can alter the receptor structure and its auto‐activation, which can modify the signal transduction and, consequently, the cell cycle regulation. For this reason, this polymorphism has been extensively investigated as a candidate marker for breast cancer (BC). In this context, the aim of this study was to evaluate the possible influence of HER2 Ile655Val in BC susceptibility and prognostic factors in a Brazilian population.

Methods

Polymorphism genotype was assessed through RFLP‐PCR in 107 BC patients with clinicopathological data available and in 150 women with no evidence of neoplasia and with no familial history of BC as control group. Association between this polymorphism and BC susceptibility and clinical parameters was evaluated through odds ratio (OR) and chi‐squared or Fisher's exact test, respectively.

Results

A significant negative association between valine allele and BC susceptibility in dominant model was found (OR 0.5; 95% CI 0.27‐0.93, P = .036). No significant association was found in relation to BC clinicopathological features (tumor size, lymph nodes commitment, histological grade, HER2 overexpression, hormonal receptors, p53, and Ki‐67).

Conclusion

Although this polymorphism did not demonstrate potential as a prognostic marker, it may be a suitable susceptibility marker for BC.

     

The LPA gene C93T polymorphism influences plasma lipoprotein(a) levels and is independently associated with susceptibility to peripheral arterial disease

BACKGROUND: Plasma lipoprotein(a) [Lp(a)] levels are mainly genetically determined. The C93T polymorphism is a naturally occurring variant of the LPA gene that may influence Lp(a) concentration. The role of Lp(a) in the pathogenesis of peripheral arterial disease (PAD) has not been firmly established. METHODS: A total of 299 patients with PAD and 312 PAD-free control subjects were investigated. Genotyping of the LPA C93T polymorphism was performed by means of PCR-RFLPs. Plasma Lp(a) levels were determined by ELISA. RESULTS: Subjects carrying at least one LPA 93T allele had lower Lp(a) levels. The prevalence rate of the 93T allele was significantly higher in control subjects (19.5%) than in PAD patients (13.0%, P=0.012). In multivariate logistic regression analysis with covariates including traditional risk factors, the 93T allele was independently associated with a reduced risk of PAD (OR=0.75, 95% CI=0.51-0.95, P=0.031). CONCLUSION: The 93T allele of the LPA gene is associated with a reduced risk of PAD and low Lp(a) levels.     

Association of MMP-3 5A/6A gene polymorphism with susceptibility to carotid atherosclerosis

ObjectivesStromelysin-1 (MMP-3) as a key member of metalloproteinase family could have an important role in atherogenesis. The 5A/6A polymorphism in the promoter of MMP-3 gene affects the level of MMP-3 gene expression. We assessed whether the MMP-3 promoter low- and high-activity genotypes are related to susceptibility for carotid atherosclerosis (CA) in Serbian population.Design and methodsThe study group of case-control design consisted of 515 participants. The 265 patients with ultrasonographic evidence of carotid plaque presence were recruited for the study. The 5A/6A polymorphism was typed by RFLP-PCR.ResultsThere was significantly higher prevalence of genotypes containing 6A allele in the patients with CA compared to controls (p < 0.05). The model of inheritance with the dominant effect of 6A allele gave elevated and significant OR for carotid atherosclerosis (adjusted OR 2.35, CI = 1.0–5.5, p = 0.048).ConclusionsSubjects carrying genotypes with 6A allele had significantly higher susceptibility to carotid atherosclerosis.     

A common polymorphism in the ABCB11 gene is associated with advanced fibrosis in hepatitis C but not in non-alcoholic fatty liver disease

Chronic HCV (hepatitis C virus)-associated cirrhosis represents a major indication for liver transplantation. Bile acids contribute to hepatic stellate cell activation as a key event in fibrogenesis. The aim of the present study was to investigate the role of bile acids and polymorphisms in bile acid level-regulating genes on fibrosis progression. A total of 206 subjects with chronic HCV infection were included for ABCB11 (ATP-binding cassette, subfamily B, member II) 1331T>C and NR1H4 (nuclear receptor) -1G>T genotyping, 178 of which were analysed for fibrosis stage. Exclusion criteria were HBV (hepatitis B virus) or HIV coinfection, alcohol >40 g/day and morbid obesity. A total of 358 patients with NAFLD (non-alcoholic fatty liver disease) were genotyped for comparison with a non-viral liver disease. Caucasian individuals (n = 110), undergoing liver resection for focal hepatic metastasis, served as controls. The ABCB11 1331C allele was significantly overrepresented in HCV patients compared with controls {allelic frequency 62.9%; OR (odds ratio), 1.41 [95% CI (confidence interval), 1.012-1.965]}. Median plasma bile acid levels were not significantly increased in the CC compared with TT genotype [7.2 (1-110) μmol/l compared with 3.5 (1-61) μmol/l; values are medians (range). A significant association between the presence of cirrhosis and ABCB11 genotype (CC compared with CT or TT, P=0.047) was observed in the χ2 test and independent of other risk factors of age, gender, body mass index and disease duration in multivariate analysis (P = 0.010). No such association could be observed in fatty liver patients with regard to advanced fibrosis (F ≥ 2). The common ABCB11 1331CC genotype, which is present in 40% of HCV patients and renders the carrier susceptible to increased bile acid levels, is associated with cirrhosis.     

A common polymorphism in the renin angiotensin system is associated with differential outcome of antihypertensive pharmacotherapy prescribed to Brazilian older women

BACKGROUND: Since variations on the renin angiotensin (RA) system tend to exert effects on blood pressure, we investigated the association of the common ACE and AT1R polymorphisms with response to a multivariate pharmacotherapy. METHODS: This prospective study involved 169 hypertensive, community-dwelling older women. Genotypes were obtained by length analysis or direct sequencing of PCR products. Blood pressure-lowering pharmacotherapy was conducted according to current Brazilian Guidelines on Hypertension. RESULTS: Genotype frequencies were in agreement to the Hardy-Weinberg equilibrium. Interventions were found to represent actual hypertension-management practices in Brazil, and accounted for a significant reduction in both systolic (P<0.001) and diastolic (P<0.001) blood pressure. Concerning the effect of polymorphisms, no influence of the ACE and AT1R genotypes were found on the magnitude of the treatment-induced blood pressure reduction (P>0.05). Nonetheless, the clinical result varied according to the ACE alleles since mean systolic pressure was roughly 10 mm Hg higher in insertion (I) homozygotes than in the deletion (D) counterparts either in baseline (P=0.001) and endpoint (P=0.010). CONCLUSION: The outcome of the antihypertensive pharmacotherapy advocated by national guidelines was significantly influenced by the ACE I/D polymorphism but not by the AT1R 1166 A/C polymorphism among postmenopausal women.     

Genetic risk factors associated with Creutzfeld-Jakob disease in Slovenians and a rapid typing for PRNP codon 129 single nucleotide polymorphism

PRNP has been the most informative marker for the predisposition to variant Creutzfeld-Jakob disease (vCJD). All victims of the vCJD carried methionine (M) at the position 129 of the PrP. Prions could travel through the immune system to get from the gut to the brain, and human leucocyte antigens (HLAs) could be involved in this carriage, with HLA-DQ7 being less efficient. Contradictory reports have raised the question of the influence of sampling in population studies. We developed a fast and reliable real-time polymerase chain reaction for codon 129 single nucleotide polymorphism (SNP) using TaqMan technology, which overcomes the main drawbacks of other methods and analysed Slovenian population (n = 97). The comparison with other populations served for the estimation of the genetic risk for the development of vCJD in Slovenians. The frequencies at the codon 129 SNP in the Slovenian population were 43.3% M, 45.4% M/V 11.3% V. Considerable differences between the DQ7 frequencies in diverse samples from the same population can be seen, especially when compared to Slovenian population. This could be because of the diverse criteria for including subjects into the study and the sampling of geographically distinct subpopulations. Analysing the adequacy of HLA-DQ7 as a possible predictive factor for developing Creutzfeld-Jakob disease (CJD) by case - control studies could be improved with exact and equal sampling of groups of patients and controls. CJD genetic risk factors in the Slovenians were not found significantly different than those in British.     

A common polymorphism in exon 46 of the human autosomal dominant polycystic kidney disease 1 gene (PKD1)

Autosomal dominant polycystic kidney disease (ADPKD) is one of the most common single gene diseases in humans. We have identified a synonymous T to C transition polymorphism in exon 46 of the PKD1 gene (12838T→C, Pro4209Pro). The polymorphism was present with similar frequencies in ADPKD patients and unaffected individuals. The heterozygosity, determined in 89 Italian individuals, was 0·347. The frequency of the rarer allele was 0·222. This polymorphism is easy to determine as it abolishes a naturally occurring DdeI restriction site. The availability of an additional intragenic marker in the PKD1 gene will improve the accuracy of linkage studies in ADPKD families.     

TLR5激动剂鞭毛蛋白预防小鼠异基因造血干细胞移植后急性移植物抗宿主病的初步研究

本研究旨在探讨Toll样受体(TLR5)激动剂鞭毛蛋白(flagellin)对小鼠异基因造血干细胞移植(allo-HSCT)后急性移植物抗宿主病(aGVHD)的预防作用和可能作用机制。用主要组织相容性抗原完全不合的纯种近交系小鼠〔供体鼠:雄性C57BL∕6鼠;受体鼠:雌性BALB∕c鼠〕建立allo-HSCT的aGVHD动物模型。受鼠随机分为3组:鞭毛蛋白组,于移植前后2次尾静脉注射高纯度(纯度≥95%)的鞭毛蛋白50μl〔5μg∕(只.次)〕预防aGVHD;单纯移植组,移植后仅给予等容量PBS;单纯照射组,仅照射不移植,亦给予等容量PBS。观察比较移植后aGVHD的表现。结果表明,移植小鼠均出现典型的aGVHD症状,单纯移植组小鼠死亡高峰在移植后第4-5天。用鞭毛蛋白作为aGVHD预防方案小鼠的aGVHD症状明显减轻,平均生存时间较单纯移植组显著延长(P<0.05)。三组小鼠移植前外周血白细胞数比较均无显著性差异,但在照射后第14、21天,鞭毛蛋白组较单纯移植组外周血白细胞数显著性升高(P<0.05)。鞭毛蛋白预防组移植小鼠aGVHD病理表现较单纯移植组明显减轻。流式细胞仪检测鞭毛蛋白组与单纯移植组移植前后不同时间点Treg细胞/CD4+T细胞含量结果也表明,移植后2-4周鞭毛蛋白组小鼠的Treg细胞数较单纯移植组明显增加(P<0.05)。结论:鞭毛蛋白对小鼠allo-HSCT后发生aGVHD有预防作用,能减轻其症状和病理损害程度,显著延长其平均生存时间,其机制有可能通过增加移植后小鼠的Treg细胞含量,从而有效改善并减轻移植后小鼠aGVHD。     

p53 codon72基因多态性与人乳头瘤病毒相关食管鳞癌遗传易感性研究的Meta分析

目的运用Meta分析的方法综合评价p53 codon72基因多态性与人乳头瘤病毒(HPV)相关食管鳞癌的关系。方法系统检索Pub Med、中国期刊网全文数据库和万方数据知识服务平台文献,并辅以文献追溯等方法,收集截至2016年3月国内外公开发表的关于p53 codon72基因多态性与HPV相关食管鳞癌研究的文献。采用Stata 11.0软件进行统计分析,对各项研究结果进行异质性检验,以合并OR值及95%可信区间(95%CI)为效应指标,同时进行敏感性分析。结果共纳入8篇文献,其中6篇病例对照研究,2篇单纯病例研究,纳入研究的病例553例,对照354名。HPV感染阳性人群患食管鳞癌的风险是HPV感染阴性人群的15.35倍[95%CI(2.33,101.23),P<0.05];p53 codon72基因多态性与食管鳞癌发生的易感性有一定的相关性[OR=1.38,95%CI(1.09,1.77),P<0.05],Arg/Arg基因型可增加患HPV相关食管鳞癌的风险[OR=1.82,95%CI(1.28,2.59),P<0.05];在食管鳞癌患者中,Arg等位基因携带者感染HPV的风险是Pro等位基因携带者的1.97倍[95%CI(1.49,2.61),P<0.05]。结论 p53 Arg72Pro基因多态性与HPV相关食管鳞癌的发生相关,携带等位基因Arg或Arg/Arg纯合基因型是HPV相关食管鳞癌的高危因素。在食管鳞癌患者中,p53codon72Arg等位基因和HPV感染具有共存性。     

P53 codon 72 polymorphism and susceptibility to development of human papilloma virus-associated cervical cancer in Indian women

BACKGROUND: Infection with human papilloma virus (HPV) is an important etiological factor in the development of cervical cancer and it has been proposed that individuals homozygous for Arg/Arg at codon-72 of p53 are seven times more susceptible to HPV-mediated cancer. In this study, we have analyzed the genetic predisposition of the India population to HPV infection and cervical carcinogenesis. METHODS: We investigated 71 cases of squamous cell carcinoma of the cervix, 14 cases of low-grade squamous intraepithelial lesions, 25 cases of high-grade squamous intraepithelial lesions and 29 noncancer controls for presence of HPV16/18 infections by L-1-specific PCR assay and Southern hybridization, and its association with polymorphism at p53 codon 72. RESULTS: We observed that 69.1% (76/110) of the cervical cancer patients were HPV positive, among which the presence of HPV16, 18 and 16/18 coinfection was 40.9%, 8.2% and 13.6%, respectively. The allele frequencies of the three p53 genotypes Arg/Arg, Arg/Pro and Pro/Pro in the HPV-positive tumour samples were 0.34, 0.57 and 0.09 in comparison with frequencies of 0.18, 0.44 and 0.38 for HPV-negative tumours. Hence, there is a significant difference in the allelic frequency of p53 Arg/Arg in high-risk HPV-infected cervical carcinoma cases (0.34) and HPV-negative carcinomas (0.18). CONCLUSION: Our results indicate a striking over-representation of homozygous arginine at codon 72 of p53 in HPV-associated cervical carcinogenesis. We conclude that women with Arg/Arg homozygous allele are more prone to infection by HPV16/18, which leads to cervical carcinomas having poor prognosis.     

The serotonin transporter gene polymorphism is associated with the susceptibility and the pain severity in Idiopathic Trigeminal Neuralgia patients

Background

To investigate the possible association between the serotonin transporter gene (5-HTTLPR) and rs 25531 polymorphism and the susceptibility and the pain severity in Trigeminal Neuralgia patients.

Methods

A total of 244 TN patients and 280 age and sex matched healthy volunteer were recruited. 5-HTTLPR and rs 25531 genotyping were performed. All patients received the carbamazepine treatment and the treatment response was evaluated at 6 months.

Results

The genotype distribution of 5-HTTLPR between TN patients and controls were significantly different. The TN Patients had a higher prevalence of short-short genotype than controls. The short-short genotype carriers are also significantly associated with higher pain severity and poorer carbamazepine treatment response compared to the long-long genotype carriers. In contrast, the rs 25531 polymorphism was not associated with the susceptibility to TN, neither with the pain severity and the treat response to carbamazepine.

Conclusion

The 5-HTTLPR polymorphism is associated with the susceptibility to TN and pain severity of TN.     

A common CYP1B1 polymorphism is associated with 2-OHE1/16-OHE1 urinary estrone ratio.

Cytochrome P450 (CYP) is a multigene family of enzymes involved in important life functions; some of these genes are inducible and are implicated in the oxidative metabolic activation and detoxification of many endogenous and exogenous compounds. CYP1B1 codes for an enzyme that catalyses the production of a 2- and 4-hydroxyl group in estrone and estradiol, while CYP1A1 catalyzes the 2-hydroxylation of estradiol in endometrium. The two genes were evaluated in a cohort of 150 subjects: African-American women had significantly lower 2-hydroxyl estrone/16-hydroxyl estrone (2-OHE1/16-OHE1) urinary metabolite ratios than Caucasian women (2.06+/-1.05 vs. 1.43+/-0.56; p=0.0002). A common polymorphism in the CYP1B1 gene (leucine to valineat codon 432) was associated with changes in urinary estrogen levels: both Caucasian and African-American women carrying the variant allele showed higher urinary metabolite ratios than women with the wild-type allele. No effect of the CYP1A1 MspI was observed. The 4-OHE1/2-OHE1 ratio was lower in subjects carrying the variant allele (Leu). The percentage change in 2-OHE1/16-OHE1 urinary ratio after indole treatment was significant in both Caucasian and African-American women carrying the wild-type CYP1B1 genotype, although it was more evident in African-Americans than in Caucasians. These results suggest that the Leu/Val CYP1B1 polymorphism may modify estradiol metabolism.