Common variants in the ATP2B1 gene are associated with susceptibility to hypertension: the Japanese Millennium Genome Project.

Hypertension is one of the most common complex genetic disorders. We have described previously 38 single nucleotide polymorphisms (SNPs) with suggestive association with hypertension in Japanese individuals. In this study we extend our previous findings by analyzing a large sample of Japanese individuals (n=14 105) for the most associated SNPs. We also conducted replication analyses in Japanese of susceptibility loci for hypertension identified recently from genome-wide association studies of European ancestries. Association analysis revealed significant association of the ATP2B1 rs2070759 polymorphism with hypertension (P=5.3×10(-5); allelic odds ratio: 1.17 [95% CI: 1.09 to 1.26]). Additional SNPs in ATP2B1 were subsequently genotyped, and the most significant association was with rs11105378 (odds ratio: 1.31 [95% CI: 1.21 to 1.42]; P=4.1×10(-11)). Association of rs11105378 with hypertension was cross-validated by replication analysis with the Global Blood Pressure Genetics consortium data set (odds ratio: 1.13 [95% CI: 1.05 to 1.21]; P=5.9×10(-4)). Mean adjusted systolic blood pressure was highly significantly associated with the same SNP in a meta-analysis with individuals of European descent (P=1.4×10(-18)). ATP2B1 mRNA expression levels in umbilical artery smooth muscle cells were found to be significantly different among rs11105378 genotypes. Seven SNPs discovered in published genome-wide association studies were also genotyped in the Japanese population. In the combined analysis with replicated 3 genes, FGF5 rs1458038, CYP17A1, rs1004467, and CSK rs1378942, odds ratio of the highest risk group was 2.27 (95% CI: 1.65 to 3.12; P=4.6×10(-7)) compared with the lower risk group. In summary, this study confirmed common genetic variation in ATP2B1, as well as FGF5, CYP17A1, and CSK, to be associated with blood pressure levels and risk of hypertension.

Gene frequencies of plasminogen in Switzerland.

Plasminogen (PLG) polymorphism was studied by agarose gel electrophoresis and immunofixation in 308 unrelated individuals from Switzerland. The gene frequencies observed were: PLG 1 = 0.69, PLG 2 = 0.28, and rare alleles = 0.03.

Interleukin-1 receptor antagonist gene (IL-1RN) polymorphism is a predictive factor of clinical pregnancy after IVF.

BACKGROUND: Only 25% of IVF transfer cycles lead to a clinical pregnancy, calling for continued technical progress but also more in depth analysis of patients' individual characteristics. The interleukin-1 (IL-1) system and matrix metalloproteinases (MMPs) are strongly implicated in embryo implantation. The genes coding for IL-1Ra (gene symbol IL-1RN), IL-1beta, MMP2 and MMP9 bear functional polymorphisms. We analysed the maternal genetic profile at these polymorphic sites in IVF patients, to determine possible correlations with IVF outcome. METHODS: One hundred and sixty women undergoing an IVF cycle were enrolled and a buccal smear was obtained. The presence of IL-1RN variable number of tandem repeats and IL-1B + 3953, MMP2-1306 and MMP9-1562 single nucleotide substitutions were determined. Patients were divided into pregnancy failures (119), biochemical pregnancies (8) and clinical pregnancies (33). RESULTS: There was a 40% decrease in IL-1RN*2 allele frequency (P = 0.024) and a 45% decrease in IL-1RN*2 carrier status in the clinical pregnancy group as compared to the pregnancy failure group (P = 0.017). This decrease was still statistically significant after a multivariate logistic regression analysis. The likelihood of a clinical pregnancy was decreased accordingly in IL-1RN*2 carriers: odds ratio = 0.349, 95% confidence interval = 0.2-0.8, P = 0.017. The IL-1B, MMP2 and MMP9 polymorphisms showed no correlation with IVF outcome. CONCLUSIONS: IL-1RN*2 allele carriage is associated with a poor prognosis of achieving a pregnancy after IVF.

Mutation screening of the urocortin gene: identification of new single nucleotide polymorphisms and association studies with obesity in French Caucasians.

A linkage between obesity-related phenotypes and the 2p21-23 locus has been reported previously. The urocortin (UCN) gene resides at this interval, and its protein decreases appetite behavior, suggesting that UCN may be a candidate gene for susceptibility to obesity. We localized the UCN gene by radiation hybrid mapping, and the surrounding markers were genotyped in a collection of French families. Evidence for linkage was shown between the marker D2S165 and leptin levels (LOD score, 1.34; P = 0.006) and between D2S2247 and the z-score of body mass index (LOD score, 1.829; P = 0.0019). The gene was screened for SNPs in 96 obese patients. Four new variants were established. Two single nucleotide polymorphisms were located in the promoter (-535 A-->G, -286 G-->A), one in intron 1 (+31 C-->G), and one in the 3'-untranslated region (+34 C-->T). Association studies in cohorts of 722 unrelated obese and 381 control subjects and transmission disequilibrium tests, performed for the two frequent promoter polymorphisms, in 120 families (894 individuals) showed that no association was present between these variants and obesity, obesity-related phenotypes, and diabetes. Thus, our analyses of the genetic variations of the UCN gene suggest that, at least in French Caucasians, they do not represent a major cause of obesity.

Schizophrenia and oxidative stress: glutamate cysteine ligase modifier as a susceptibility gene.

Oxidative stress could be involved in the pathophysiology of schizophrenia, a major psychiatric disorder. Glutathione (GSH), a redox regulator, is decreased in patients' cerebrospinal fluid and prefrontal cortex. The gene of the key GSH-synthesizing enzyme, glutamate cysteine ligase modifier (GCLM) subunit, is strongly associated with schizophrenia in two case-control studies and in one family study. GCLM gene expression is decreased in patients' fibroblasts. Thus, GSH metabolism dysfunction is proposed as one of the vulnerability factors for schizophrenia.

Functional studies of a germ-line polymorphism at codon 47 within the p53 gene.

A rare germ-line polymorphism in codon 47 of the p53 gene replaces the wild-type proline (CCG) with a serine (TCG). Restriction analysis of 101 human samples revealed the frequency of the rare allele to be 0% (n = 69) in Caucasians and 4.7% (3/64, n = 32) among African-Americans. To investigate the consequence of this amino acid substitution, a cDNA construct (p53 mut47ser) containing the mutation was introduced into a lung adenocarcinoma cell line (Calu-6) that does not express p53. A growth suppression similar to that obtained after introduction of a wild-type p53 cDNA construct was observed, in contrast to the result obtained by introduction of p53 mut143ala. Furthermore, expression of neither p53 mut47ser nor wild-type p53 was tolerated by growing cells. In transient expression assays, both mut47ser and wild-type p53 activated the expression of a reporter gene linked to a p53 binding sequence (PG13-CAT) and inhibited the expression of the luciferase gene under the control of the Rous sarcoma virus promoter (RSVluc). In the same assay, mut143ala did not activate the expression of PG13-CAT and produced only a slight inhibitory effect on RSVluc. These findings indicate that the p53 variant with a serine at codon 47 should be considered as a rare germ-line polymorphism that does not alter the growth-suppression activity of p53.

Effects of CSN3 and LGB gene polymorphisms on production traits in beef cattle

The objective of the present study was to estimate the allele and genotype frequencies of the CSN3/Hinfl and LGB/HaeIII gene polymorphisms in beef cattle belonging to different genetic groups, and to determine the effects of these polymorphisms on growth and carcass traits in these animals, which are submitted to an intensive production model. Genotyping was performed on 79 Nelore, 30 Canchim (5/8 Charolais + 3/8 Zebu) and 275 crossbred cattle originating from the crosses of Simmental (n = 30) and Angus (n = 245) sires with Nelore females. Body weight, weight gain, dressing percentage, longissimus dorsi area and backfat thickness were fitted using the GLM procedure, and least square means of the genotypes were compared by the F test. The results showed that the CSN3/Hinfl and LGB/HaeIII polymorphisms did not have any effect on growth or carcass traits (p > 0.05). Copyright by the Brazilian Society of genetics.

Identification and frequency of transposable elements in Eucalyptus

Transposable elements (TE) are major components of eukaryotic genomes and involved in cell regulation and organism evolution. We have analyzed 123,889 expressed sequence tags of the Eucalyptus Genome Project database and found 124 sequences representing 76 TE in 9 groups, of which copia, MuDR and FAR1 groups were the most abundant. The low amount of sequences of TE may reflect the high efficiency of repression of these elements, a process that is called TE silencing. Frequency of groups of TE in Eucalyptus libraries which were prepared with different tissues or physiologic conditions from seedlings or adult plants indicated that developing plants experience the expression of a much wider spectrum of TE groups than that seen in adult plants. These are preliminary results that identify the most relevant TE groups involved with Eucalyptus development, which is important for industrial wood production. Copyright by the Brazilian Society of Genetics.

HFE gene mutations in Brazilian thalassemic patients

Hereditary hemochromatosis is a disorder of iron metabolism characterized by increased iron intake and progressive storage and is related to mutations in the HFE gene. Interactions between thalassemia and hemochromatosis may further increase iron overload. The ethnic background of the Brazilian population is heterogeneous and studies analyzing the simultaneous presence of HFE and thalassemia-related mutations have not been carried out. The aim of this study was to evaluate the prevalence of the H63D, S65C and C282Y mutations in the HFE gene among 102 individuals with alpha-thalassemia and 168 beta-thalassemia heterozygotes and to compare them with 173 control individuals without hemoglobinopathies. The allelic frequencies found in these three groups were 0.98, 2.38, and 0.29% for the C282Y mutation, 13.72, 13.70, and 9.54% for the H63D mutation, and 0, 0.60, and 0.87% for the S65C mutation, respectively. The chi-square test for multiple independent individuals indicated a significant difference among groups for the C282Y mutation, which was shown to be significant between the beta-thalassemia heterozygote and the control group by the Fisher exact test (P value = 0.009). The higher frequency of inheritance of the C282Y mutation in the HFE gene among beta-thalassemic patients may contribute to worsen the clinical picture of these individuals. In view of the characteristics of the Brazilian population, the present results emphasize the need to screen for HFE mutations in beta-thalassemia carriers.

Frequency of the HFE C282Y and H63D polymorphisms in Brazilian malaria patients and blood donors from the Amazon region

Malaria is an endemic parasitosis and its causitive agent, Plasmodium, has a metabolism linked to iron supply. HFE is a gene with the polymorphisms C282Y and H63D, which are associated with a progressive iron accumulation in the organism leading to a disease called hereditary hemochromatosis. The aim of the present study was to determine the allelic and genotypic frequencies of the HFE gene polymorphisms in malaria patients and blood donors from the Brazilian Amazon region. We screened 400 blood donors and 400 malaria patients for the HFE C282Y and H63D polymorphisms from four states of the Brazilian Amazon region by polymerase chain reaction and restriction fragment length polymorphism analysis. We did not find any C282Y homozygous individuals, and the only five heterozygous individuals detected were from Pará State. The most frequent genotype in the North region of Brazil was the H63D heterozygote, in both study groups. Our results contribute to the concept that the Brazilian Amazon region should not be regarded as a single entity in South America. These polymorphisms did not influence the symptoms of malaria in the population studied, as neither severe signs nor high parasitemia were observed. Therefore, different hereditary hemochromatosis diagnostic and control measures must be developed and applied within its diverse locations. Investigations are currently being carried out in our laboratory in order to determine the importance of the coexistence of hereditary hemochromatosis in patients affected by parasitic diseases, such as malaria. ©FUNPEC-RP.

DNA repair gene polymorphism is associated with the genetic basis of atherosclerotic coronary artery disease

Background: Atherosclerotic coronary artery disease (CAD) is a multifactorial process that appears to be caused by the interaction of environmental risk factors with multiple predisposing genes. It is nowadays accepted that increased levels of DNA damage induced by xenobiotics play an important role in the early phases of atherogenesis. Therefore, in this study, we focus on determining whether genetic variations in xenobiotic-metabolizing [glutathione-S-transferase theta 1 (GSTT1), glutathione-S-transferase mu 1 (GSTM1), cytochrome P450 IIEI (CYP2E1)] and DNA repair [X-ray cross-complementing group 1 (XRCC1)] genes might be associated with increased risk for CAD. Methods: A case-control study was conducted with 400 individuals who underwent subjected to coronary angiography. A total of 299 were patients diagnosed with effective coronary atherosclerosis (case group; >20% obstructive lesion), and 101 (control group) were individuals diagnosed as negative for CAD (<20% obstructive lesions). The polymorphism identifications for GSTM1 and GSTT1, and for CYP2E1 and XRCC1 genes were performed by polymerase chain reaction (PCR) amplification and by PCR-RFLP, respectively. Results and conclusions: The XRCC1 homozygous wild-type genotype Arg/Arg for codon 399 was statistically less pronounced in the case subjects (21.4%) than in controls (38.5%); individuals with the variant XRCC1 genotype had a 2.3-fold increased risk for coronary atherosclerosis than individuals with the wild-type genotype (OR=2.3, 95% CI=1.13-4.69). Conversely, no association between GSTM1, GSTT1, and CYP2E1gene polymorphisms and coronary atherosclerosis was detected. The results provide evidence of the role of DNA damage and repair in cardiovascular disease. © 2011 Elsevier Inc. All rights reserved.

Variation in the CXCR1 gene (IL8RA) is not associated with susceptibility to chronic periodontitis

Background: The chemokine receptor 1 CXCR-1 (or IL8R-alpha) is a specific receptor for the interleukin 8 (IL-8), which is chemoattractant for neutrophils and has an important role in the inflammatory response. The polymorphism rs2234671 at position Ex2+860G > C of the CXCR1 gene causes a conservative amino acid substitution (S276T). This single nucleotide polymorphism (SNP) seemed to be functional as it was associated with decreased lung cancer risk. Previous studies of our group found association of haplotypes in the IL8 and in the CXCR2 genes with the multifactorial disease chronic periodontitis. In this study we investigated the polymorphism rs2234671 in 395 Brazilian subjects with and without chronic periodontitis. Findings. Similar distribution of the allelic and genotypic frequencies were observed between the groups (p > 0.05). Conclusions: The polymorphism rs2234671 in the CXCR1 gene was not associated with the susceptibility to chronic periodontitis in the studied Brazilian population. © 2011 Scarel-Caminaga et al; licensee BioMed Central Ltd.

Effect of exercise training on the cardiovascular and biochemical parameters in women with eNOS gene polymorphism

Context: Presence of endothelial nitric oxide synthase (eNOS) gene polymorphism has been associated with cardiovascular disease (CVD) whereas exercise training (EX) promotes beneficial effects on CVD which is related to increased nitric oxide levels (NO). Objective: To evaluate if women with eNOS gene polymorphism at position-G894T would be less responsive to EX than those who did not carry T allele. Methods: Women were trained 3 days/week, 40 minutes session during 6 months. Cardio-biochemical parameters and genetic analysis were performed in a double-blind fashion. Results: Plasma NOx - levels were similar in both groups at baseline (GG genotype: 18.44±3.28 μM) and (GT + TT genotype: 17.19±2.43 μM) and after EX (GG: 29.20±4.33 and GT+TT: 27.38±3.12 μM). A decrease in blood pressure was also observed in both groups. Discussion and conclusion: The presence of eNOS polymorphism does not affect the beneficial effects of EX in women. © 2011 Informa UK, Ltd.

Profiles of gene polymorphisms in cytokines and toll-like receptors with higher risk for gastric cancer

Background: Chronic inflammation and gastric carcinogenesis show a close association, so gene polymorphisms that modify the intensity of the inflammatory response may contribute to variations in gastric cancer risk. Aims: The purpose of this study was to investigate the combined effect of the pro- and anti-inflammatory cytokines and toll-like receptors polymorphisms on the chronic gastritis and gastric cancer risk in a Brazilian population sample. Methods: We evaluated 669 DNA samples (200 of gastric cancer [GC], 229 of chronic gastritis [CG], and 240 of healthy individuals [C]). Ten polymorphisms were genotyped: IL-1RN and TLR2 -196 to -174 del using the allele-specific PCR method and TNF-A (rs1800629; rs1799724), TNF-B (rs909253), IL-8 (rs4073; rs2227532), IL-10 (rs1800872) and TLR4 (rs4986790; rs4986791) using PCR-RFLP. Results: Polymorphisms TNF-A-308G/A, IL-8-251A/T, TNF-B + 252A/G and TLR4 + 1196C/T were not associated with risk of any gastric lesion. However, an association with increased risk for GC was observed for polymorphisms IL-1RNL/2 (p < 0.001), TNF-A-857C/T (p = 0.022), IL-8-845T/C (p < 0.001), IL-10-592C/A (p < 0.001), TLR2ins/del (p < 0.001), and TLR4 + 896A/G (p = 0.033). In CG, an association was observed only with polymorphisms IL-1RNL/2 and IL-10-592A/C (p < 0.001 for both). A combined analysis of these six polymorphisms associated with GC revealed a profile with two to four combined genotypes which confer a higher risk of gastric carcinogenesis, with an OR increased 2.95-fold to 50.4-fold, highlighting the combinations IL-1RN2/TNF-A-857T/IL-8-845C, IL-1RN2/IL-8-845C/TLR2del, IL-1RN2/IL-10-592A/TLR4 + 896G, IL-10-592A/TLR2del/ TLR4 + 896G, and IL-1RN2/TNFA-857T/IL8-845C/TLR2del. Conclusions: Our findings evidenced that the combined effect of polymorphisms in genes involved in the inflammatory process may potentiate the risk of gastric cancer, thus emphasizing the importance of evaluating multiple polymorphisms together. © 2012 Springer Science+Business Media New York.

Association of the Leptin Gene with Carcass Characteristics in Nellore Cattle

Advances in DNA technology have created biotechnological tools that can be used in animal selection and new strategies for increasing herd productivity and quality. The objective of the present work was to associate the genotypes of leptin gene exon 2 polymorphisms with productive traits in Nellore cattle. Blood was collected from Nellore males and PCR-RFLP reactions were performed with the restriction enzymes ClaI and Kpn2I. The gene frequencies resulting from digestion by ClaI were 0.60 and 0.40 for allele A and T, respectively; the genotypic frequencies were AA = 0.20 and AT = 0.80. The gene frequencies from digestion by Kpn2I were 0.81 for allele C and 0.194 for allele T; the genotypic frequencies were CC = 0.62 and CT = 0.38. The populations in both cases were not in Hardy-Weinberg equilibrium (p > 0.05), and the TT genotype was not found. Significant associations were noted between leptin gene exon 2 polymorphisms and five productive traits in Nellore cattle: carcass fat distribution, the intensity of red muscle coloration, pH, marbling, and post-slaughter fat thickness. © 2013 Copyright Taylor and Francis Group, LLC.