Sample records for cag repeat polymorphism

  1. Androgen receptor polymorphism (CAG repeats) and androgenicity.

    Canale, D; Caglieresi, C; Moschini, C; Liberati, C D; Macchia, E; Pinchera, A; Martino, E


    Objective Polymorphism of the androgen receptor (AR) has been related to various pathophysiological conditions, such as osteoporosis and infertility. The objectives of this study were to evaluate the frequency of distribution in a normal Italian population and to assess CAG repeats (CAGr) in other conditions, such as hypoandrogenism, potentially influenced by AR polymorphism. Patients and measurements CAGr polymorphism was determined in a group of 91 healthy normoandrogenized subjects, 29 hypoandrogenized patients (hypoplasia of prostate and seminal vesicles, reduced beard or body hair, etc.) and 29 infertile patients by direct sequencing. Results The mean (+/- SD) number of CAG repeats [(CAGr)n] was 21.5 (+/- 1.7) in the control group, 21.4 (+/- 2.0) in the infertile patients and 24.0 (+/- 2.9) in the hypoandrogenic males. The difference was statistically significant between this last group and the other two (P CAGr repeats was 38% among hypoandrogenized patients, 7% among infertile patients and 5% among the control group. In hypoandrogenized subjects (CAGr)n correlated slightly with testis and prostate volume. The number of CAG repeats was not associated with any of the hormonal parameters, including testosterone, evaluated in the three groups. Conclusions Our normal population, representing subjects from Central Italy, is superimposable on other European populations with regard to (CAGr)n distribution. Hypoandrogenic males have a shift in the frequency distribution towards longer (CAGr)n. Infertile patients are not statistically different from the control group. These findings suggest that, given the same amount of circulating testosterone, as in our hypoandrogenized and control group, the final net androgenic phenotypical effect is due to AR polymorphism. PMID:16117826

  2. The DRPLA CAG repeats in an Italian population sample: evaluation of the polymorphism for forensic applications.

    Pelotti, S; Mantovani, V; Esposti, P D; D'Apote, L; Bragliani, M; Maiolini, E; Abbondanza, A; Pappalardo, G


    The DRPLA CAG repeats polymorphism has been studied in an Italian population sample. PCR amplification, manual PAGE and silver staining were employed. A total of 16 different alleles, spanning the range from 5 to 21 CAG triplettes, was observed. The heterozygosity was 0.81 and no significant deviation from Hardy-Weinberg equilibrium was found 81 meioses from parentage testing were also analyzed and a Mendelian pattern of inheritance was observed in all cases. In addition, we could successfully type DRPLA locus in some forensic specimens, 1 ng of DNA allowing clear definition of alleles. The authors conclude that the DRPLA CAG repeats analysis may be useful for forensic applications. PMID:9544554

  3. Positive association of the androgen receptor CAG repeat length polymorphism with the risk of prostate cancer.

    Paz-Y-Miño, César; Robles, Paulo; Salazar, Carolina; Leone, Paola E; García-Cárdenas, Jennyfer M; Naranjo, Manuel; López-Cortés, Andrés


    Prostate cancer (PC) is the most frequently diagnosed cancer in Ecuador (15.6%). The androgen receptor gene codes for a protein that has an androgen‑binding domain, DNA‑binding domain and N‑terminal domain, which contains two polymorphic trinucleotide repeats (CAG and GGC). The aim of the present study was to determine whether variations in the number of repetitions of CAG and GGC are associated with the pathological features and the risk of developing PC. The polymorphic CAG and GGC repeat lengths in 108 mestizo patients with PC, 148 healthy mestizo individuals, and 78 healthy indigenous individuals were examined via a retrospective case‑control study. Genotypes were determined by genomic sequencing. The results demonstrated that patients with ≤21 CAG repeats have an increased risk of developing PC [odds ratio (OR)=2.99, 95% confidence interval (CI) =1.79‑5.01; P<0.001]. The presence of ≤21 CAG repeats was also associated with a tumor stage ≥T2c (OR=4.75; 95% CI=1.77‑12.72; P<0.005) and a Gleason score ≥7 (OR=2.9; 95% CI=1.1‑7.66; P=0.03). In addition, the combination of ≤21 CAG and ≥17 GGC repeats was associated with the risk of developing PC (OR=2.42; 95% CI=1.38‑4.25; P=0.002) and with tumor stage ≥T2c (OR=2.77; 95% CI=1.13‑6.79; P=0.02). In conclusion, the histopathological characteristics and PC risk in Ecuadorian indigenous and mestizo populations differs in association with the CAG repeats, and the combination of CAG and GGC repeats. PMID:27357524

  4. Androgen Receptor CAG Repeat Polymorphism and Epigenetic Influence among the South Indian Women with Polycystic Ovary Syndrome

    Shilpi Dasgupta; Pisapati V S Sirisha; Kudugunti Neelaveni; Kathragadda Anuradha; Alla G Reddy; Kumarasamy Thangaraj; B Mohan Reddy


    The present study was carried out to assess the role of androgen receptor CAG repeat polymorphism and X chromosome inactivation (XCI) pattern among Indian PCOS women and controls which has not been hitherto explored and also to test the hypothesis that shorter CAG alleles would be preferentially activated in PCOS. CAG repeat polymorphism and X chromosome methylation patterns were compared between PCOS and non-PCOS women. 250 PCOS women and 299 controls were included for this study. Androgen r...

  5. MSH3 polymorphisms and protein levels affect CAG repeat instability in Huntington's disease mice.

    Stéphanie Tomé

    Full Text Available Expansions of trinucleotide CAG/CTG repeats in somatic tissues are thought to contribute to ongoing disease progression through an affected individual's life with Huntington's disease or myotonic dystrophy. Broad ranges of repeat instability arise between individuals with expanded repeats, suggesting the existence of modifiers of repeat instability. Mice with expanded CAG/CTG repeats show variable levels of instability depending upon mouse strain. However, to date the genetic modifiers underlying these differences have not been identified. We show that in liver and striatum the R6/1 Huntington's disease (HD (CAG∼100 transgene, when present in a congenic C57BL/6J (B6 background, incurred expansion-biased repeat mutations, whereas the repeat was stable in a congenic BALB/cByJ (CBy background. Reciprocal congenic mice revealed the Msh3 gene as the determinant for the differences in repeat instability. Expansion bias was observed in congenic mice homozygous for the B6 Msh3 gene on a CBy background, while the CAG tract was stabilized in congenics homozygous for the CBy Msh3 gene on a B6 background. The CAG stabilization was as dramatic as genetic deficiency of Msh2. The B6 and CBy Msh3 genes had identical promoters but differed in coding regions and showed strikingly different protein levels. B6 MSH3 variant protein is highly expressed and associated with CAG expansions, while the CBy MSH3 variant protein is expressed at barely detectable levels, associating with CAG stability. The DHFR protein, which is divergently transcribed from a promoter shared by the Msh3 gene, did not show varied levels between mouse strains. Thus, naturally occurring MSH3 protein polymorphisms are modifiers of CAG repeat instability, likely through variable MSH3 protein stability. Since evidence supports that somatic CAG instability is a modifier and predictor of disease, our data are consistent with the hypothesis that variable levels of CAG instability associated with

  6. The impact of the CAG repeat polymorphism of the androgen receptor gene on muscle and adipose tissues in 20-29-year-old Danish men: Odense Androgen Study

    Nielsen, Torben Leo; Hagen, Claus; Wraae, Kristian;


    The number of CAG repeats (CAG(n)) within the CAG repeat polymorphism of the androgen receptor gene correlates inversely with the transactivation of the receptor.......The number of CAG repeats (CAG(n)) within the CAG repeat polymorphism of the androgen receptor gene correlates inversely with the transactivation of the receptor....

  7. Searching for association of the CAG repeat polymorphism in the mitochondrial DNA polymerase gamma gene (POLG) with colorectal cancer.

    Linkowska, Katarzyna; Jawień, Arkadiusz; Marszałek, Andrzej; Skonieczna, Katarzyna; Grzybowski, Tomasz


    Mitochondrial DNA polymerase gamma (POLG) is the only DNA polymerase involved in maintaining the mitochondrial genome. Recent studies demonstrated an association of CAG repeat polymorphism in the second exon of POLG gene with the risk of cancer. We investigated the CAG repeat variability in the POLG gene in tumor and non-tumor tissues from colorectal cancer patients and in DNA samples isolated from blood obtained from age-matched healthy persons. Somatically occuring CAG-repeat alterations in cancer tissues have been observed in 10% of patients, but no association has been found between the CAG repeat variants in the POLG gene and colorectal cancer risk. PMID:26317126

  8. Genetic Association Between Androgen Receptor Gene CAG Repeat Length Polymorphism and Male Infertility: A Meta-Analysis.

    Pan, Bihui; Li, Rui; Chen, Yao; Tang, Qiuqin; Wu, Wei; Chen, Liping; Lu, Chuncheng; Pan, Feng; Ding, Hongjuan; Xia, Yankai; Hu, Lingqing; Chen, Daozhen; Sha, Jiahao; Wang, Xinru


    The association between polymorphism of androgen receptor gene CAG (AR-CAG) and male infertility in several studies was controversial. Based on studies on association between AR-CAG repeat length and male infertility in recent years, an updated meta-analysis is needed. We aimed to evaluate the association between AR-CAG repeat length and male infertility in advantage of the data in all published reports.We searched for reports published before August 2015 using PubMed, CNKI, VIP, and WanFang. Data on sample size, mean, and standard deviation (SD) of AR-CAG repeat length were extracted independently by 3 investigators.Forty-four reports were selected based on criteria. The overall infertile patients and azoospermic patients were found to have longer AR-CAG repeat length (standard mean difference (SMD) = 0.19, 95% confidence interval (CI): 0.10-0.28, P < 0.01; SMD = 0.36, 95% CI: 0.10-0.61, P < 0.01). AR-CAG repeat length was longer in infertile men in Asian, Caucasian, and mixed races (SMD = 0.25, 95% CI: 0.08-0.43, P <0.01; SMD = 0.13, 95% CI: 0.02-0.25, P <0.05; SMD = 0.39, 95% CI: 0.15-0.63, P <0.01). The overall study shows that increased AR-CAG repeat length was associated with male infertility. The subgroup study on races shows that increased AR-CAG repeat length was associated with male infertility in Asian, Caucasian, and mixed races. Increased AR-CAG repeat length was also associated with azoospermia.This meta-analysis supports that increased androgen receptor CAG length is capable of causing male infertility susceptibility. PMID:26962784

  9. The androgen receptor CAG repeat polymorphism and modification of breast cancer risk in BRCA1 and BRCA2 mutation carriers

    The androgen receptor (AR) gene exon 1 CAG repeat polymorphism encodes a string of 9–32 glutamines. Women with germline BRCA1 mutations who carry at least one AR allele with 28 or more repeats have been reported to have an earlier age at onset of breast cancer. A total of 604 living female Australian and British BRCA1 and/or BRCA2 mutation carriers from 376 families were genotyped for the AR CAG repeat polymorphism. The association between AR genotype and disease risk was assessed using Cox regression. AR genotype was analyzed as a dichotomous covariate using cut-points previously reported to be associated with increased risk among BRCA1 mutation carriers, and as a continuous variable considering smaller allele, larger allele and average allele size. There was no evidence that the AR CAG repeat polymorphism modified disease risk in the 376 BRCA1 or 219 BRCA2 mutation carriers screened successfully. The rate ratio associated with possession of at least one allele with 28 or more CAG repeats was 0.74 (95% confidence interval 0.42–1.29; P = 0.3) for BRCA1 carriers, and 1.12 (95% confidence interval 0.55–2.25; P = 0.8) for BRCA2 carriers. The AR exon 1 CAG repeat polymorphism does not appear to have an effect on breast cancer risk in BRCA1 or BRCA2 mutation carriers

  10. Relationships among androgen receptor CAG repeat polymorphism, sex hormones and penile length in Han adult men from China:a cross-sectional study

    YanMin Ma; DaLin He; KaiJie Wu; Liang Ning; Jin Zeng; Bo Kou; HongJun Xie; ZhenKun Ma; XinYang Wang; YongGuang Gong


    This study aimed to investigate the correlations among androgen receptor (AR) CAG repeat polymorphism, sex hormones and penile length in healthy Chinese young adult men. Two hundred and iffty-three healthy men (aged 22.8 ± 3.1 years) were enrolled. The individuals were grouped as CAG short (CAGS) if they harbored repeat length of≤20 or as CAG long (CAGL) if their CAG repeat length was>20. Body height/weight, penile length and other parameters were examined and recorded by the speciifed physicians;CAG repeat polymorphism was determined by the polymerase chain reaction (PCR) method;and the serum levels of the sex hormones were detected by radioimmunoassay. Student’s t-test or linear regression analysis was used to assess the associations among AR CAG repeat polymorphism, sex hormones and penile length. This investigation showed that the serum total testosterone (T) level was positively associated with the AR CAG repeat length (P= 0.01); whereas, no signiifcant correlation of T or AR CAG repeat polymorphism with the penile length was found (P= 0.593). Interestingly, an inverse association was observed between serum prolactin (PRL) levels and penile length by linear regression analyses (b=-0.024, P= 0.039, 95%conifdence interval (CI):-0.047, 0). Collectively, this study provides the ifrst evidence that serum PRL, but not T or AR CAG repeat polymorphism, is correlated with penile length in the Han adult population from northwestern China.

  11. Association analysis of a highly polymorphic CAG Repeat in the human potassium channel gene KCNN3 and migraine susceptibility

    Ovcaric Mick


    Full Text Available Abstract Background Migraine is a polygenic multifactorial disease, possessing environmental and genetic causative factors with multiple involved genes. Mutations in various ion channel genes are responsible for a number of neurological disorders. KCNN3 is a neuronal small conductance calcium-activated potassium channel gene that contains two polyglutamine tracts, encoded by polymorphic CAG repeats in the gene. This gene plays a critical role in determining the firing pattern of neurons and acts to regulate intracellular calcium channels. Methods The present association study tested whether length variations in the second (more 3' polymorphic CAG repeat in exon 1 of the KCNN3 gene, are involved in susceptibility to migraine with and without aura (MA and MO. In total 423 DNA samples from unrelated individuals, of which 202 consisted of migraine patients and 221 non-migraine controls, were genotyped and analysed using a fluorescence labelled primer set on an ABI310 Genetic Analyzer. Allele frequencies were calculated from observed genotype counts for the KCNN3 polymorphism. Analysis was performed using standard contingency table analysis, incorporating the chi-squared test of independence and CLUMP analysis. Results Overall, there was no convincing evidence that KCNN3 CAG lengths differ between Caucasian migraineurs and controls, with no significant difference in the allelic length distribution of CAG repeats between the population groups (P = 0.090. Also the MA and MO subtypes did not differ significantly between control allelic distributions (P > 0.05. The prevalence of the long CAG repeat (>19 repeats did not reach statistical significance in migraineurs (P = 0.15, nor was there a significant difference between the MA and MO subgroups observed compared to controls (P = 0.46 and P = 0.09, respectively, or between MA vs MO (P = 0.40. Conclusion This association study provides no evidence that length variations of the second polyglutamine array in

  12. Androgen receptor CAG repeats length polymorphism and the risk of polycystic ovarian syndrome (PCOS.

    Singh Rajender

    Full Text Available OBJECTIVE: Polycystic ovarian syndrome (PCOS refers to an inheritable androgen excess disorder characterized by multiple small follicles located at the ovarian periphery. Hyperandrogenism in PCOS, and inverse correlation between androgen receptor (AR CAG numbers and AR function, led us to hypothesize that CAG length variations may affect PCOS risk. METHODS: CAG repeat region of 169 patients recruited following strictly defined Rotterdam (2003 inclusion criteria and that of 175 ethnically similar control samples, were analyzed. We also conducted a meta-analysis on the data taken from published studies, to generate a pooled estimate on 2194 cases and 2242 controls. RESULTS: CAG bi-allelic mean length was between 8.5 and 24.5 (mean = 17.43, SD = 2.43 repeats in the controls and between 11 and 24 (mean = 17.39, SD = 2.29 repeats in the cases, without any significant difference between the two groups. Further, comparison of bi-allelic mean and its frequency distribution in three categories (short, moderate and long alleles did not show any significant difference between controls and various case subgroups. Frequency distribution of bi-allelic mean in two categories (extreme and moderate alleles showed over-representation of extreme sized alleles in the cases with marginally significant value (50.3% vs. 61.5%, χ(2 = 4.41; P = 0.036, which turned insignificant upon applying Bonferroni correction for multiple comparisons. X-chromosome inactivation analysis showed no significant difference in the inactivation pattern of CAG alleles or in the comparison of weighed bi-allelic mean between cases and controls. Meta-analysis also showed no significant correlation between CAG length and PCOS risk, except a minor over-representation of short CAG alleles in the cases. CONCLUSION: CAG bi-allelic mean length did not differ between controls and cases/case sub-groups nor did the allele distribution. Over-representation of short

  13. Association of the polymorphism of the CAG repeat in the mitochondrial DNA polymerase gamma gene (POLG) with testicular germ-cell cancer

    Blomberg Jensen, M; Leffers, H; Petersen, J H;


    of the common 10-CAG-long POLG allele with testicular cancer as well as previously reported in some European populations' association with male subfertility, which is a condition carrying an increased risk of TGCT. PATIENTS AND METHODS: The number of CAG repeats in both POLG alleles was established in 243...... patients with TGCT and in 869 controls by the analysis of the genomic DNA fragment. RESULTS: A significantly higher proportion of men homozygous allele of other than the common 10 CAG repeats was found among the patients with TGCT in comparison to the controls (4.9% versus 1.3%, respectively, P = 0.......001). The vast majority of the homozygous patients had a seminoma (11 of 12; 97%), despite that only about half (55%) of the studied patients had this tumour type. CONCLUSIONS: The findings indicate that the POLG polymorphism may be a contributing factor in the pathogenesis of TGCT particularly in seminoma...

  14. No effects of androgen receptor gene CAG and GGC repeat polymorphisms on digit ratio (2D:4D): Meta-analysis

    Voracek, Martin


    Objectives: A series of meta-analyses assessed whether differentially efficacious variants (CAG and GGC repeat-length polymorphisms) of the human androgen receptor gene are associated with digit ratio (2D:4D), a widely investigated putative pointer to prenatal androgen action. Methods: Extensive literature search strategies identified a maximum of 16 samples (total N = 2157) eligible for meta-analysis. Results: In contrast to a small-sample (N = 50) initial report, widely cited affirmatively ...

  15. Sequence analysis of the CCG polymorphic region adjacent to the CAG triplet repeat of the HD gene in normal and HD chromosomes.

    Pêcheux, C; Mouret, J F; Dürr, A.; Agid, Y; Feingold, J; Brice, A; Dodé, C; Kaplan, J.C.


    The CAG expansion responsible for Huntington's disease (HD) is followed by an adjacent polymorphic CCG repeat region which may interfere with a PCR based diagnosis. We have sequenced this region in 52 unrelated HD patients, from both normal and HD chromosomes. Fifty percent of the normal alleles were (CCG)7(CCT)2, 48% (CCG)10(CCT)2, and 2% (CCG)7(CCT)3. In contrast (CCG)7(CCT)2 was found in 85% of the HD alleles which represents significant linkage disequilibrium with the HD mutation.

  16. Contributions by the CAG-repeat Polymorphism of the Androgen Receptor Gene and Circulating Androgens to Muscle Size. Odense Androgen Study - A Population-based Study of 20-29 Year-old Danish Men

    Nielsen, Torben Leo; Hagen, Claus; Wraae, Kristian;


    Context: The number of CAG-repeats within the CAG-repeat polymorphism of the androgen receptor gene is inversely correlated with the transcriptional activity of the androgen receptor. Objective: To study the effect of the CAG-repeat number and circulating androgens on muscle size, to examine the...... CAG-repeat number in relation to body fat mass and circulating androgens, and to identify the best hormonal marker of low muscle size amongst total testosterone, bioavailable testosterone, and dihydrotestosterone. Design, Setting, and Participants: Population-based study of 783 Danish men aged 20......-repeat number correlated inversely with thigh and axial muscle area and with lower and upper extremity lean body mass. Except for upper extremity lean body mass, these findings remained significant in multivariate analyses controlling for circulating androgens, physical activity, smoking, alcohol intake...

  17. How strong is the association between CAG and GGN repeat length polymorphisms in the androgen receptor gene and prostate cancer risk?

    Zeegers, M.P.; Kiemeney, L.A.L.M.; Nieder, A.M.; Ostrer, H.


    OBJECTIVE: Although narrative reviews have suggested an association between (CAG)n and (GGN)n polymorphisms in the AR gene and prostate cancer, it has never been quantified systematically. The purpose of this meta-analysis was to provide relative and absolute quantitative summary estimates with suff

  18. Androgen receptor CAG polymorphism and the risk of benign prostatic hyperplasia in a Brazilian population

    Vanderlei Biolchi


    Full Text Available Benign prostatic hyperplasia (BPH is a very frequent age-related proliferative abnormality in men. Polymorphic CAG repeat in the androgen receptor (AR can alter transactivation of androgen-responsive genes and potentially influence BPH risk. We investigated the association between CAG repeat length and risk of BPH in a case-control study of a Brazilian population. We evaluated 214 patients; 126 with BPH and 88 healthy controls. DNA was extracted from peripheral leucocytes and the AR gene was analyzed using fragment analysis. Hazard ratio (HR and 95% confidence interval were estimated using logistic regression models. Mean CAG length was not different between patients with BPH and controls. The CAG repeat length was examined as a categorical variable (CAG 21 and CAG 22 and did not differ between the control vs. the BPH group. We found no evidence for an association between AR CAG repeat length in BPH risk in a population-based sample of Brazilians.

  19. Size matters: Associations between the androgen receptor CAG repeat length and the intrafollicular hormone milieu

    Borgbo, T; Macek, M; Chrudimska, J;


    Granulosa cell (GC) expressed androgen receptors (AR) and intrafollicular androgens are central to fertility. The transactivating domain of the AR contains a polymorphic CAG repeat sequence, which is linked to the transcriptional activity of AR and may influence the GC function. This study aims to...... expression compared to medium CAG repeat lengths (P = 0.03). In conclusion, long CAG repeat lengths in the AR were associated to significant attenuated levels of androgens and an increased conversion of testosterone into oestradiol, in human small antral follicles....

  20. An Expanded CAG Repeat in Huntingtin Causes +1 Frameshifting.

    Saffert, Paul; Adamla, Frauke; Schieweck, Rico; Atkins, John F; Ignatova, Zoya


    Maintenance of triplet decoding is crucial for the expression of functional protein because deviations either into the -1 or +1 reading frames are often non-functional. We report here that expression of huntingtin (Htt) exon 1 with expanded CAG repeats, implicated in Huntington pathology, undergoes a sporadic +1 frameshift to generate from the CAG repeat a trans-frame AGC repeat-encoded product. This +1 recoding is exclusively detected in pathological Htt variants, i.e. those with expanded repeats with more than 35 consecutive CAG codons. An atypical +1 shift site, UUC C at the 5' end of CAG repeats, which has some resemblance to the influenza A virus shift site, triggers the +1 frameshifting and is enhanced by the increased propensity of the expanded CAG repeats to form a stem-loop structure. The +1 trans-frame-encoded product can directly influence the aggregation of the parental Htt exon 1. PMID:27382061

  1. Discrepancies in reporting the CAG repeat lengths for Huntington's disease

    Quarrell, Oliver W; Handley, Olivia; O'Donovan, Kirsty;


    Huntington's disease results from a CAG repeat expansion within the Huntingtin gene; this is measured routinely in diagnostic laboratories. The European Huntington's Disease Network REGISTRY project centrally measures CAG repeat lengths on fresh samples; these were compared with the original resu...

  2. The impact of the CAG repeat polymorphism of the androgen receptor gene on muscle and adipose tissues in 20-29-year-old Danish men: Odense Androgen Study

    Nielsen, Torben Leo; Hagen, Claus; Wraae, Kristian;


    .108), and relative LBMtotal (r=–0.082), and positively with relative SATthigh (r=0.137), relative SATlower trunk (r=0.188), relative FMlower extremity (r=0.107), and relative FMtotal (r=0.082). These relationships remained significant, controlling for physical activity, smoking, chronic disease, and age. CAGn did...... not correlate with any circulating androgen. Conclusions: The CAG repeat polymorphism affects body composition in young men: absolute musclethigh and absolute musclelower trunk increase as CAGn decreases. Expressed relatively, muscle areas and LBM increase, while SAT and FM decrease as CAGn decreases...

  3. In Vitro Expansion of CAG, CAA, and Mixed CAG/CAA Repeats

    Grzegorz Figura; Edyta Koscianska; Krzyzosiak, Wlodzimierz J.


    Polyglutamine diseases, including Huntington’s disease and a number of spinocerebellar ataxias, are caused by expanded CAG repeats that are located in translated sequences of individual, functionally-unrelated genes. Only mutant proteins containing polyglutamine expansions have long been thought to be pathogenic, but recent evidence has implicated mutant transcripts containing long CAG repeats in pathogenic processes. The presence of two pathogenic factors prompted us to attempt to distinguis...

  4. Counting CAG repeats in the Huntington’s disease gene by restriction endonuclease EcoP15I cleavage

    Moencke-Buchner, E.; Reich, S.; Muecke, M.; M. Reuter; Messer, W; Wanker, E E; Krueger, D.H.


    Huntington's disease (HD) is a progressive neurodegenerative disorder with autosomal-dominant inheritance. The disease is caused by a CAG trinucleotide repeat expansion located in the first exon of the HD gene. The CAG repeat is highly polymorphic and varies from 6 to 37 repeats on chromosomes of unaffected individuals and from more than 30 to 180 repeats on chromosomes of HD patients. In this study, we show that the number of CAG repeats in the HD gene can be determined by restriction of the...

  5. Androgen Receptor CAG Repeat Length Is Associated With Body Fat and Serum SHBG in Boys

    Mouritsen, Annette; Hagen, Casper P; Sørensen, Kaspar;


    to evaluate associations between the AR (CAG)n polymorphism and development of pubic hair, levels of androgens, and body fat content in healthy boys. Methods: A longitudinal study of 78 healthy boys (age 6.2-12.4 years at inclusion) from the COPENHAGEN Puberty Study was conducted with clinical...... examinations and blood samples drawn every 6 months. The AR (CAG)n length was established by direct DNA sequencing and reproductive hormones were measured in serum by standardized analyses. Results: Median AR (CAG)n length was 22 (range, 17-30). Before puberty (at 10 years of age), boys with long CAG repeats...... (CAG ≥24) had lower levels of SHBG (88 vs 125 nmol/L) (P <.05) and a nonsignificant trend toward higher median skinfold thickness (41 vs 31 mm) (P = .06) compared with boys with an average number of CAG repeats (CAG 21-23). In contrast, the inverse association was observed at puberty (at 12 years of...

  6. Germ-line CAG repeat instability causes extreme CAG repeat expansion with infantile-onset spinocerebellar ataxia type 2

    Vinther-Jensen, Tua; Ek, Jakob; Duno, Morten;


    The spinocerebellar ataxias (SCA) are a genetically and clinically heterogeneous group of diseases, characterized by dominant inheritance, progressive cerebellar ataxia and diverse extracerebellar symptoms. A subgroup of the ataxias is caused by unstable CAG-repeat expansions in their respective...

  7. Methylation of HpaII and HhaI sites near the polymorphic CAG repeat in the human androgen-receptor gene correlates with X chromosome inactivation

    Allen, R.C.; Zoghbi, H.Y.; Moseley, A.B.; Rosenblatt, H.M.; Belmont, J.W. (Baylor College of Medicine, Houston (United States))


    The human androgen-receptor gene (HUMARA; GenBank) contains a highly polymorphic trinucleotide repeat in the first exon. The authors have found that the methylation of HpaII and HhaI sites less than 100 pb away from this polymorphic short tandem repeat (STR) correlates with X inactivation. The close proximity of the restriction-enzyme sites to the STR allows the development of a PCR assay that distinguishes between the maternal and paternal alleles and identifies their methylation status. The accuracy of this assay was tested on (a) DNA from hamster/human hybrid cell lines containing either an active or inactive human X chromosome; (b) DNA from normal males and females; and (c) DNA from females showing nonrandom patterns of X inactivation. Data obtained using this assay correlated substantially with those obtained using the PGK, HPRT, and M27[beta] probes, which detect X inactivation patterns by Southern blot analysis. In order to demonstrate one application of this assay, the authors examined X inactivation patterns in the B lymphocytes of potential and obligate carriers of X-linked agammaglobulinemia. 42 refs., 5 figs., 1 tab.

  8. Non-linear association between androgen receptor CAG and GGN repeat lengths and reproductive parameters in fertile European and Inuit men

    Brokken, L J S; Rylander, L; Jönsson, B A;


    Recently the dogma that there is an inverse linear association between androgen receptor (AR) CAG and GGN polymorphisms and receptor activity has been challenged. We analysed the pattern of association between 21 male reproductive phenotypes and AR CAG/GGN repeat lengths in 557 proven-fertile men...

  9. No CAG repeat expansion of polymerase gamma is associated with male infertility in Tamil Nadu, South India

    J Poongothai


    Full Text Available Mitochondria contains a single deoxyribonucleic acid (DNA polymerase, polymerase gamma (POLG mapped to long arm of chromosome 15 (15q25, responsible for replication and repair of mitochondrial DNA. Exon 1 of the human POLG contains CAG trinucleotide repeat, which codes for polyglutamate. Ten copies of CAG repeat were found to be uniformly high (0.88 in different ethnic groups and considered as the common allele, whereas the mutant alleles (not -10/not -10 CAG repeats were found to be associated with oligospermia/oligoasthenospermia in male infertility. Recent data suggested the implication of POLG CAG repeat expansion in infertility, but are debated. The aim of our study was to explore whether the not -10/not -10 variant is associated with spermato g enic failure. As few study on Indian population have been conducted so far to support this view, we investigated the distribution of the POLG CAG repeats in 61 infertile men and 60 normozoospermic control Indian men of Tamil Nadu, from the same ethnic background. This analysis interestingly revealed that the homozygous wild type genotype (10/-10 was common in infertile men (77% - 47/61 and in normozoospermic control men (71.7% - 43/60. Our study failed to confirm any influence of the POLG gene polymorphism on the efficiency of the spermatogenesis.

  10. CAG repeat expansion in Huntington disease determines age at onset in a fully dominant fashion

    Lee, J-M; Ramos, E M; Lee, J-H; Gillis, T; Mysore, J S; Hayden, M R; Warby, S C; Morrison, P; Nance, M; Ross, C A; Margolis, R L; Squitieri, F; Orobello, S; Di Donato, S; Gomez-Tortosa, E; Ayuso, C; Suchowersky, O; Trent, R J A; McCusker, E; Novelletto, A; Frontali, M; Jones, R; Ashizawa, T; Frank, S; Saint-Hilaire, M H; Hersch, S M; Rosas, H D; Lucente, D; Harrison, M B; Zanko, A; Abramson, R K; Marder, K; Sequeiros, J; Paulsen, J S; Landwehrmeyer, G B; Myers, R H; MacDonald, M E; Gusella, J F; Hasholt, Lis Frydenreich; Nørremølle, Anne; Nielsen, Jørgen Erik


    Age at onset of diagnostic motor manifestations in Huntington disease (HD) is strongly correlated with an expanded CAG trinucleotide repeat. The length of the normal CAG repeat allele has been reported also to influence age at onset, in interaction with the expanded allele. Due to profound...

  11. Discrepancies in reporting the CAG repeat lengths for Huntington's disease.

    Quarrell, Oliver W; Handley, Olivia; O'Donovan, Kirsty; Dumoulin, Christine; Ramos-Arroyo, Maria; Biunno, Ida; Bauer, Peter; Kline, Margaret; Landwehrmeyer, G Bernhard


    Huntington's disease results from a CAG repeat expansion within the Huntingtin gene; this is measured routinely in diagnostic laboratories. The European Huntington's Disease Network REGISTRY project centrally measures CAG repeat lengths on fresh samples; these were compared with the original results from 121 laboratories across 15 countries. We report on 1326 duplicate results; a discrepancy in reporting the upper allele occurred in 51% of cases, this reduced to 13.3% and 9.7% when we applied acceptable measurement errors proposed by the American College of Medical Genetics and the Draft European Best Practice Guidelines, respectively. Duplicate results were available for 1250 lower alleles; discrepancies occurred in 40% of cases. Clinically significant discrepancies occurred in 4.0% of cases with a potential unexplained misdiagnosis rate of 0.3%. There was considerable variation in the discrepancy rate among 10 of the countries participating in this study. Out of 1326 samples, 348 were re-analysed by an accredited diagnostic laboratory, based in Germany, with concordance rates of 93% and 94% for the upper and lower alleles, respectively. This became 100% if the acceptable measurement errors were applied. The central laboratory correctly reported allele sizes for six standard reference samples, blind to the known result. Our study differs from external quality assessment (EQA) schemes in that these are duplicate results obtained from a large sample of patients across the whole diagnostic range. We strongly recommend that laboratories state an error rate for their measurement on the report, participate in EQA schemes and use reference materials regularly to adjust their own internal standards. PMID:21811303

  12. A pathogenic mechanism in Huntington's disease involves small CAG-repeated RNAs with neurotoxic activity.

    Mónica Bañez-Coronel

    Full Text Available Huntington's disease (HD is an autosomal dominantly inherited disorder caused by the expansion of CAG repeats in the Huntingtin (HTT gene. The abnormally extended polyglutamine in the HTT protein encoded by the CAG repeats has toxic effects. Here, we provide evidence to support that the mutant HTT CAG repeats interfere with cell viability at the RNA level. In human neuronal cells, expanded HTT exon-1 mRNA with CAG repeat lengths above the threshold for complete penetrance (40 or greater induced cell death and increased levels of small CAG-repeated RNAs (sCAGs, of ≈21 nucleotides in a Dicer-dependent manner. The severity of the toxic effect of HTT mRNA and sCAG generation correlated with CAG expansion length. Small RNAs obtained from cells expressing mutant HTT and from HD human brains significantly decreased neuronal viability, in an Ago2-dependent mechanism. In both cases, the use of anti-miRs specific for sCAGs efficiently blocked the toxic effect, supporting a key role of sCAGs in HTT-mediated toxicity. Luciferase-reporter assays showed that expanded HTT silences the expression of CTG-containing genes that are down-regulated in HD. These results suggest a possible link between HD and sCAG expression with an aberrant activation of the siRNA/miRNA gene silencing machinery, which may trigger a detrimental response. The identification of the specific cellular processes affected by sCAGs may provide insights into the pathogenic mechanisms underlying HD, offering opportunities to develop new therapeutic approaches.

  13. Distinct repeat motifs at the C-terminal region of CagA of Helicobacter pylori strains isolated from diseased patients and asymptomatic individuals in West Bengal, India

    Chattopadhyay Santanu


    Full Text Available Abstract Background Infection with Helicobacter pylori strains that express CagA is associated with gastritis, peptic ulcer disease, and gastric adenocarcinoma. The biological function of CagA depends on tyrosine phosphorylation by a cellular kinase. The phosphate acceptor tyrosine moiety is present within the EPIYA motif at the C-terminal region of the protein. This region is highly polymorphic due to variations in the number of EPIYA motifs and the polymorphism found in spacer regions among EPIYA motifs. The aim of this study was to analyze the polymorphism at the C-terminal end of CagA and to evaluate its association with the clinical status of the host in West Bengal, India. Results Seventy-seven H. pylori strains isolated from patients with various clinical statuses were used to characterize the C-ternimal polymorphic region of CagA. Our analysis showed that there is no correlation between the previously described CagA types and various disease outcomes in Indian context. Further analyses of different CagA structures revealed that the repeat units in the spacer sequences within the EPIYA motifs are actually more discrete than the previously proposed models of CagA variants. Conclusion Our analyses suggest that EPIYA motifs as well as the spacer sequence units are present as distinct insertions and deletions, which possibly have arisen from extensive recombination events. Moreover, we have identified several new CagA types, which could not be typed by the existing systems and therefore, we have proposed a new typing system. We hypothesize that a cagA gene encoding higher number EPIYA motifs may perhaps have arisen from cagA genes that encode lesser EPIYA motifs by acquisition of DNA segments through recombination events.

  14. Unusual structures are present in DNA fragments containing super-long Huntingtin CAG repeats.

    Daniel Duzdevich

    Full Text Available BACKGROUND: In the R6/2 mouse model of Huntington's disease (HD, expansion of the CAG trinucleotide repeat length beyond about 300 repeats induces a novel phenotype associated with a reduction in transcription of the transgene. METHODOLOGY/PRINCIPAL FINDINGS: We analysed the structure of polymerase chain reaction (PCR-generated DNA containing up to 585 CAG repeats using atomic force microscopy (AFM. As the number of CAG repeats increased, an increasing proportion of the DNA molecules exhibited unusual structural features, including convolutions and multiple protrusions. At least some of these features are hairpin loops, as judged by cross-sectional analysis and sensitivity to cleavage by mung bean nuclease. Single-molecule force measurements showed that the convoluted DNA was very resistant to untangling. In vitro replication by PCR was markedly reduced, and TseI restriction enzyme digestion was also hindered by the abnormal DNA structures. However, significantly, the DNA gained sensitivity to cleavage by the Type III restriction-modification enzyme, EcoP15I. CONCLUSIONS/SIGNIFICANCE: "Super-long" CAG repeats are found in a number of neurological diseases and may also appear through CAG repeat instability. We suggest that unusual DNA structures associated with super-long CAG repeats decrease transcriptional efficiency in vitro. We also raise the possibility that if these structures occur in vivo, they may play a role in the aetiology of CAG repeat diseases such as HD.

  15. Helicobacter pylori CagA protein polymorphisms and their lack of association with pathogenesis

    Nicole; Acosta; Andrés; Quiroga; Pilar; Delgado; María; Mercedes; Bravo; Carlos; Jaramillo


    AIM: To investigate Helicobacter pylori (H. pylori) CagA diversity and to evaluate the association between protein polymorphisms and the occurrence of gastric pathologies. METHODS: One hundred and twenty-two clinical isolates of H. pylori cultured from gastric biopsies obtained from Colombian patients with dyspepsia were included as study material. DNA extracted from isolates was used to determine cagA status, amplifying the C-terminal cagA gene region by polymerase chain reaction. One hundred and six strai...

  16. Assessment of Correlation between Androgen Receptor CAG Repeat Length and Infertility in Infertile Men Living in Khuzestan, Iran

    Saeid Reza Khatami


    Full Text Available Background: The androgen receptor (AR gene contains a polymorphic trinucleotide repeat that encodes a polyglutamine tract in its N-terminal transactivation domain (NTAD. We aimed to find a correlation between the length of this polymorphic tract and azoospermia or oligozoospermia in infertile men living in Khuzestan, Iran. Materials and Methods: In this case-control study during two years till 2010, we searched for microdeletions in the Y chromosome in 84 infertile male patients with normal karyotype who lived in Khuzestan Province, Southwest of Iran. All cases (n=12 of azoospermia or oligozoospermia resulting from Y chromosome microdeletions were excluded from our study. The number of CAG repeats in exon 1 of the AR gene was determined in 72 patients with azoospermia or oligozoospermia and in 72 fertile controls, using the polymerase chain reaction (PCR and polyacrylamide gel electrophoresis. Results: Microdeletions were detected in 14.3% (n=12 patients suffering severe oligozoospermia. The mean CAG repeat length was 18.99 ± 0.35 (range, 11-26 and 19.96 ± 0.54 (range, 12-25 in infertile males and controls, respectively. Also in the infertile group, the most common allele was 19 (26.38%, while in controls, it was 25 (22.22%. Conclusion: Y chromosome microdeletions could be one of the main reasons of male infertility living in Khuzestan Province, while there was no correlation between CAG length in AR gene with azoospermia or oligozoospermia in infertile men living in Khuzestan, Iran.

  17. Helicobacter pylori cagL amino acid polymorphisms and its association with gastroduodenal diseases.

    Shukla, Sanket Kumar; Prasad, Kashi Nath; Tripathi, Aparna; Jaiswal, Virendra; Khatoon, Jahanarah; Ghsohal, Uday Chand; Krishnani, Narendra; Husain, Nuzhat


    CagL is a pilus protein of Helicobacter pylori that interacts with host cellular α5β1 integrins through its arginine-glycine-aspartate (RGD) motif, guiding proper positioning of the T4SS and translocation of CagA. Deletion or sequence variations of cagL significantly diminished the ability of H. pylori to induce secretion of IL-8 by the host cell. Therefore, this study was undertaken to investigate the association of cagL and its amino acid sequence polymorphisms with gastric cancer (GC), peptic ulcer disease (PUD), and non-ulcer dyspepsia (NUD) as there are no such studies from India. In total, 200 adult patients (NUD 120, PUD 30, GC 50) who underwent an upper gastrointestinal endoscopy were enrolled. H. pylori infection was diagnosed by rapid urease test, culture, histopathology, and PCR. The collected isolates were screened for cagL genotype by PCR and assessed for amino acid sequence polymorphisms using sequence translation. The prevalence of H. pylori infection in study population was 52.5%. Most of the isolates were cagL genopositive (86.6%), and all had RGD motif in their amino acid sequences. D58 and K59 polymorphisms in cagL-genopositive strains were significantly higher in GC patients (P < 0.05). Combined D58K59 polymorphism was associated with higher risk of GC (3.8-fold) when compared to NUD. In conclusion, H. pylori cagL amino acid polymorphisms such as D58K59 are correlated with a higher risk of GC in the Indian population. Further studies are required to know the exact role of particular cagL amino acid polymorphisms in the pathogenicity of H. pylori infection. PMID:22941498

  18. Nuclear speckles are detention centers for transcripts containing expanded CAG repeats.

    Urbanek, Martyna O; Jazurek, Magdalena; Switonski, Pawel M; Figura, Grzegorz; Krzyzosiak, Wlodzimierz J


    The human genetic disorders caused by CAG repeat expansions in the translated sequences of various genes are called polyglutamine (polyQ) diseases because of the cellular "toxicity" of the mutant proteins. The contribution of mutant transcripts to the pathogenesis of these diseases is supported by several observations obtained from cellular models of these disorders. Here, we show that the common feature of cell lines modeling polyQ diseases is the formation of nuclear CAG RNA foci. We performed qualitative and quantitative analyses of these foci in numerous cellular models endogenously and exogenously expressing mutant transcripts by fluorescence in situ hybridization (FISH). We compared the CAG RNA foci of polyQ diseases with the CUG foci of myotonic dystrophy type 1 and found substantial differences in their number and morphology. Smaller differences within the polyQ disease group were also revealed and included a positive correlation between the foci number and the CAG repeat length. We show that expanded CAA repeats, also encoding glutamine, did not trigger RNA foci formation and foci formation is independent of the presence of mutant polyglutamine protein. Using FISH combined with immunofluorescence, we demonstrated partial co-localization of CAG repeat foci with MBNL1 alternative splicing factor, which explains the mild deregulation of MBNL1-dependent genes. We also showed that foci reside within nuclear speckles in diverse cell types: fibroblasts, lymphoblasts, iPS cells and neuronal progenitors and remain dependent on integrity of these nuclear structures. PMID:27239700

  19. CAG repeat expansion in Huntington disease determines age at onset in a fully dominant fashion

    Lee, J.-M.; Ramos, E.M.; Lee, J.-H.; Gillis, T.; Mysore, J.S.; Hayden, M.R.; Warby, S.C.; Morrison, P.; Nance, M.; Ross, C.A.; Margolis, R.L.; Squitieri, F.; Orobello, S.; Di Donato, S.; Gomez-Tortosa, E.; Ayuso, C.; Suchowersky, O.; Trent, R.J.A.; McCusker, E.; Novelletto, A.; Frontali, M.; Jones, R.; Ashizawa, T.; Frank, S.; Saint-Hilaire, M.H.; Hersch, S.M.; Rosas, H.D.; Lucente, D.; Harrison, M.B.; Zanko, A.; Abramson, R.K.; Marder, K.; Sequeiros, J.; Paulsen, J.S.; Landwehrmeyer, G.B.; Myers, R.H.; MacDonald, M.E.; Durr, Alexandra; Rosenblatt, Adam; Frati, Luigi; Perlman, Susan; Conneally, Patrick M.; Klimek, Mary Lou; Diggin, Melissa; Hadzi, Tiffany; Duckett, Ayana; Ahmed, Anwar; Allen, Paul; Ames, David; Anderson, Christine; Anderson, Karla; Anderson, Karen; Andrews, Thomasin; Ashburner, John; Axelson, Eric; Aylward, Elizabeth; Barker, Roger A.; Barth, Katrin; Barton, Stacey; Baynes, Kathleen; Bea, Alexandra; Beall, Erik; Beg, Mirza Faisal; Beglinger, Leigh J.; Biglan, Kevin; Bjork, Kristine; Blanchard, Steve; Bockholt, Jeremy; Bommu, Sudharshan Reddy; Brossman, Bradley; Burrows, Maggie; Calhoun, Vince; Carlozzi, Noelle; Chesire, Amy; Chiu, Edmond; Chua, Phyllis; Connell, R.J.; Connor, Carmela; Corey-Bloom, Jody; Craufurd, David; Cross, Stephen; Cysique, Lucette; Santos, Rachelle Dar; Davis, Jennifer; Decolongon, Joji; DiPietro, Anna; Doucette, Nicholas; Downing, Nancy; Dudler, Ann; Dunn, Steve; Ecker, Daniel; Epping, Eric A.; Erickson, Diane; Erwin, Cheryl; Evans, Ken; Factor, Stewart A.; Farias, Sarah; Fatas, Marta; Fiedorowicz, Jess; Fullam, Ruth; Furtado, Sarah; Garde, Monica Bascunana; Gehl, Carissa; Geschwind, Michael D.; Goh, Anita; Gooblar, Jon; Goodman, Anna; Griffith, Jane; Groves, Mark; Guttman, Mark; Hamilton, Joanne; Harrington, Deborah; Harris, Greg; Heaton, Robert K.; Helmer, Karl; Henneberry, Machelle; Hershey, Tamara; Herwig, Kelly; Howard, Elizabeth; Hunter, Christine; Jankovic, Joseph; Johnson, Hans; Johnson, Arik; Jones, Kathy; Juhl, Andrew; Kim, Eun Young; Kimble, Mycah; King, Pamela; Klimek, Mary Lou; Klöppel, Stefan; Koenig, Katherine; Komiti, Angela; Kumar, Rajeev; Langbehn, Douglas; Leavitt, Blair; Leserman, Anne; Lim, Kelvin; Lipe, Hillary; Lowe, Mark; Magnotta, Vincent A.; Mallonee, William M.; Mans, Nicole; Marietta, Jacquie; Marshall, Frederick; Martin, Wayne; Mason, Sarah; Matheson, Kirsty; Matson, Wayne; Mazzoni, Pietro; McDowell, William; Miedzybrodzka, Zosia; Miller, Michael; Mills, James; Miracle, Dawn; Montross, Kelsey; Moore, David; Mori, Sasumu; Moser, David J.; Moskowitz, Carol; Newman, Emily; Nopoulos, Peg; Novak, Marianne; O'Rourke, Justin; Oakes, David; Ondo, William; Orth, Michael; Panegyres, Peter; Pease, Karen; Perlman, Susan; Perlmutter, Joel; Peterson, Asa; Phillips, Michael; Pierson, Ron; Potkin, Steve; Preston, Joy; Quaid, Kimberly; Radtke, Dawn; Rae, Daniela; Rao, Stephen; Raymond, Lynn; Reading, Sarah; Ready, Rebecca; Reece, Christine; Reilmann, Ralf; Reynolds, Norm; Richardson, Kylie; Rickards, Hugh; Ro, Eunyoe; Robinson, Robert; Rodnitzky, Robert; Rogers, Ben; Rosenblatt, Adam; Rosser, Elisabeth; Rosser, Anne; Price, Kathy; Price, Kathy; Ryan, Pat; Salmon, David; Samii, Ali; Schumacher, Jamy; Schumacher, Jessica; Sendon, Jose Luis Lópenz; Shear, Paula; Sheinberg, Alanna; Shpritz, Barnett; Siedlecki, Karen; Simpson, Sheila A.; Singer, Adam; Smith, Jim; Smith, Megan; Smith, Glenn; Snyder, Pete; Song, Allen; Sran, Satwinder; Stephan, Klaas; Stober, Janice; Sü?muth, Sigurd; Suter, Greg; Tabrizi, Sarah; Tempkin, Terry; Testa, Claudia; Thompson, Sean; Thomsen, Teri; Thumma, Kelli; Toga, Arthur; Trautmann, Sonja; Tremont, Geoff; Turner, Jessica; Uc, Ergun; Vaccarino, Anthony; van Duijn, Eric; Van Walsem, Marleen; Vik, Stacie; Vonsattel, Jean Paul; Vuletich, Elizabeth; Warner, Tom; Wasserman, Paula; Wassink, Thomas; Waterman, Elijah; Weaver, Kurt; Weir, David; Welsh, Claire; Werling-Witkoske, Chris; Wesson, Melissa; Westervelt, Holly; Weydt, Patrick; Wheelock, Vicki; Williams, Kent; Williams, Janet; Wodarski, Mary; Wojcieszek, Joanne; Wood, Jessica; Wood-Siverio, Cathy; Wu, Shuhua; Yastrubetskaya, Olga; de Yebenes, Justo Garcia; Zhao, Yong Qiang; Zimbelman, Janice; Zschiegner, Roland; Aaserud, Olaf; Abbruzzese, Giovanni; Andrews, Thomasin; Andrich, Jurgin; Antczak, Jakub; Arran, Natalie; Artiga, Maria J. Saiz; Bachoud-Lévi, Anne-Catherine; Banaszkiewicz, Krysztof; di Poggio, Monica Bandettini; Bandmann, Oliver; Barbera, Miguel A.; Barker, Roger A.; Barrero, Francisco; Barth, Katrin; Bas, Jordi; Beister, Antoine; Bentivoglio, Anna Rita; Bertini, Elisabetta; Biunno, Ida; Bjørgo, Kathrine; Bjørnevoll, Inga


    Objective: Age at onset of diagnostic motor manifestations in Huntington disease (HD) is strongly correlated with an expanded CAG trinucleotide repeat. The length of the normal CAG repeat allele has been reported also to influence age at onset, in interaction with the expanded allele. Due to profound implications for disease mechanism and modification, we tested whether the normal allele, interaction between the expanded and normal alleles, or presence of a second expanded allele affects age at onset of HD motor signs. Methods: We modeled natural log-transformed age at onset as a function of CAG repeat lengths of expanded and normal alleles and their interaction by linear regression. Results: An apparently significant effect of interaction on age at motor onset among 4,068 subjects was dependent on a single outlier data point. A rigorous statistical analysis with a well-behaved dataset that conformed to the fundamental assumptions of linear regression (e.g., constant variance and normally distributed error) revealed significance only for the expanded CAG repeat, with no effect of the normal CAG repeat. Ten subjects with 2 expanded alleles showed an age at motor onset consistent with the length of the larger expanded allele. Conclusions: Normal allele CAG length, interaction between expanded and normal alleles, and presence of a second expanded allele do not influence age at onset of motor manifestations, indicating that the rate of HD pathogenesis leading to motor diagnosis is determined by a completely dominant action of the longest expanded allele and as yet unidentified genetic or environmental factors. Neurology® 2012;78:690–695 PMID:22323755

  20. Single cell analysis reveals gametic and tissue-specific instability of the SCA1 CAG repeat

    Chong, S.S.; McCall, A.E.; Cota, J. [Baylor College of Medicine, Houston, TX (United States)] [and others


    Spinocerebellar ataxia type 1 is an autosomal dominant neurodegenerative disease caused by expansion of a CAG trinucleotide repeat within the SCA1 gene on chromosome 6p22-23. We performed a comparative analysis of the SCA1 CAG repeat from blood and sperm of an affected male. Genomic amplification revealed a broader smear of the SCA1 allele product from sperm compared to that from peripheral blood leukocytes (PBL). To resolve this observed difference, we analyzed single sperm directly and demonstrate that the SCA1 allele in PBL is also heterogeneous, although the range of variability in allele sizes is much less than that observed in sperm. Limited genome analysis was also performed on PBL DNA from an unaffected individual with an upper normal allele of 36 repeats in parallel with an affected individual with an expanded allele of 40 repeats. The 36 repeat normal allele, which contains a CAT interruption, was completely stable compared to the uninterrupted repeat of the SCA1 allele, demonstrating a direct correlation between absence of a CAT interruption and somatic instability of the repeat. We also analyzed the size of the CAG repeat in tissues derived from various brain regions from a patient with juvenile-onset disease to determine if the size of the expansion correlated with the site of neuropathology. The results clearly show tissue-specific differences in mosaicism of repeat length. More importantly, the pattern of tissue-specific differences in repeat-length mosaicism in SCA1 within the brain parallels those seen in Huntington disease. In both disorders the expanded alleles are smaller in cerebellar tissue. These results suggest that the observed tissue-specific differences in instability of the SCA1 CAG repeat, either within the brain or between blood and sperm, are a function of the intracellular milieu or the intrinsic replicative potential of the various celltypes.

  1. Twisting right to left: A…A mismatch in a CAG trinucleotide repeat overexpansion provokes left-handed Z-DNA conformation.

    Noorain Khan


    Full Text Available Conformational polymorphism of DNA is a major causative factor behind several incurable trinucleotide repeat expansion disorders that arise from overexpansion of trinucleotide repeats located in coding/non-coding regions of specific genes. Hairpin DNA structures that are formed due to overexpansion of CAG repeat lead to Huntington's disorder and spinocerebellar ataxias. Nonetheless, DNA hairpin stem structure that generally embraces B-form with canonical base pairs is poorly understood in the context of periodic noncanonical A…A mismatch as found in CAG repeat overexpansion. Molecular dynamics simulations on DNA hairpin stems containing A…A mismatches in a CAG repeat overexpansion show that A…A dictates local Z-form irrespective of starting glycosyl conformation, in sharp contrast to canonical DNA duplex. Transition from B-to-Z is due to the mechanistic effect that originates from its pronounced nonisostericity with flanking canonical base pairs facilitated by base extrusion, backbone and/or base flipping. Based on these structural insights we envisage that such an unusual DNA structure of the CAG hairpin stem may have a role in disease pathogenesis. As this is the first study that delineates the influence of a single A…A mismatch in reversing DNA helicity, it would further have an impact on understanding DNA mismatch repair.

  2. Meta-analysis of relationship between androgen receptor CAG repeats length polymorphism and the polycystic ovary syndrome%雄激素受体(CAG)n基因多态性与多囊卵巢综合征相关性的Meta分析

    余瑞梅; 邱娜璇; 陈春敏


    目的 评价雄激素受体(androgen receptor,AR) (CAG)n基因多态性与多囊卵巢综合征(polycystic ovary syndrome,PCOS)易感性的相关性.方法 检索Pubmed、Embase、CNKI、VIP、万方数据库,英文检索词为androgen receptor,polycystic ovarian syndrome,中文检索词为雄激素受体和多囊卵巢综合征,收集有关AR (CAG)n基因多态性与PCOS易感性的病例对照研究,进行Meta分析.结果 共纳入12篇文献,PCOS组1 697例,对照组(健康女性)1 984例.Meta分析结果显示,PCOS组与对照组间AR (CAG)n重复序列长度比较,差异无统计学意义[标准化均数差(SMD)=-0.05,95%CI:-0.19~0.08,P=0.440].PCOS患者中,高雄激素血症(hyperandrogenism,HA)患者与非HA患者间AR (CAG)n重复序列长度比较,差异无统计学意义(SMD=0.56,95%CI:-0.13~1.25,P=0.110).结论 AR (CAG)n基因多态性可能与P-COS及其并发的高雄激素血症的发生无关联.

  3. Continuous and periodic expansion of CAG repeats in Huntington's disease R6/1 mice.

    Linda Møllersen

    Full Text Available Huntington's disease (HD is one of several neurodegenerative disorders caused by expansion of CAG repeats in a coding gene. Somatic CAG expansion rates in HD vary between organs, and the greatest instability is observed in the brain, correlating with neuropathology. The fundamental mechanisms of somatic CAG repeat instability are poorly understood, but locally formed secondary DNA structures generated during replication and/or repair are believed to underlie triplet repeat expansion. Recent studies in HD mice have demonstrated that mismatch repair (MMR and base excision repair (BER proteins are expansion inducing components in brain tissues. This study was designed to simultaneously investigate the rates and modes of expansion in different tissues of HD R6/1 mice in order to further understand the expansion mechanisms in vivo. We demonstrate continuous small expansions in most somatic tissues (exemplified by tail, which bear the signature of many short, probably single-repeat expansions and contractions occurring over time. In contrast, striatum and cortex display a dramatic--and apparently irreversible--periodic expansion. Expansion profiles displaying this kind of periodicity in the expansion process have not previously been reported. These in vivo findings imply that mechanistically distinct expansion processes occur in different tissues.

  4. Unstable expansion of the CAG trinucleotide repeat in MAB21L1: report of a second pedigree and effect on protein expression

    Margolis, R.; Stine, O; Ward, C.; Franz, M.; Rosenblatt, A; Callahan, C; Sherr, M.; Ross, C; Potter, N.


    MAB21L1, originally termed CAGR1, is the human homologue of the C elegans cell fate determining gene mab21. MAB21L1, mapped to 13q13, contains a highly polymorphic 5' untranslated CAG repeat that normally ranges from six to 31 triplets in length. A pedigree has been previously reported in which the repeat length is expanded to 45-50 triplets and is transmitted unstably between generations; the expansion did not correlate to a clinical phenotype but did exhibit somatic mosaicism. We now report...

  5. Replication Stalling and Heteroduplex Formation within CAG/CTG Trinucleotide Repeats by Mismatch Repair

    Viterbo, David


    Trinucleotide repeat expansions are responsible for at least two dozen neurological disorders. Mechanisms leading to these large expansions of repeated DNA are still poorly understood. It was proposed that transient stalling of the replication fork by the repeat tract might trigger slippage of the newly-synthesized strand over its template, leading to expansions or contractions of the triplet repeat. However, such mechanism was never formally proven. Here we show that replication fork pausing and CAG/CTG trinucleotide repeat instability are not linked, stable and unstable repeats exhibiting the same propensity to stall replication forks when integrated in a yeast natural chromosome. We found that replication fork stalling was dependent on the integrity of the mismatch-repair system, especially the Msh2p-Msh6p complex, suggesting that direct interaction of MMR proteins with secondary structures formed by trinucleotide repeats in vivo, triggers replication fork pauses. We also show by chromatin immunoprecipitation that Msh2p is enriched at trinucleotide repeat tracts, in both stable and unstable orientations, this enrichment being dependent on MSH3 and MSH6. Finally, we show that overexpressing MSH2 favors the formation of heteroduplex regions, leading to an increase in contractions and expansions of CAG/CTG repeat tracts during replication, these heteroduplexes being dependent on both MSH3 and MSH6. These heteroduplex regions were not detected when a mutant msh2-E768A gene in which the ATPase domain was mutated was overexpressed. Our results unravel two new roles for mismatch-repair proteins: stabilization of heteroduplex regions and transient blocking of replication forks passing through such repeats. Both roles may involve direct interactions between MMR proteins and secondary structures formed by trinucleotide repeat tracts, although indirect interactions may not be formally excluded.

  6. Serum testosterone levels and androgen receptor CAG polymorphism correlate with hepatitis B virus (HBV-related acute liver failure in male HBV carriers.

    Bao-Yan Xu

    Full Text Available BACKGROUND: Augmentation of androgen/androgen receptor (AR pathway may influence chronic hepatitis B (CHB more likely in males. AR activity is modulated by a polymorphic CAG repeat sequence in AR exon 1. This study aimed to investigate the relationship between serum testosterone levels, CAG repeat numbers and hepatitis B virus (HBV-related acute liver failure (ALF. METHODS: Three hundred and seventy eight male CHB patients with ALF and 441 asymptomatic HBV carriers (AsCs were recruited. AR CAG repeats numbers were analyzed. The serum testosterone levels of AsCs, ALFs and patients with hepatitis B flare groups, and sequential serum samples, were assessed quantitatively. RESULTS: The median CAG repeat (M-CAG frequency was significantly higher in ALF patients than AsCs (P<0.001. Patients with M-CAG alleles (P<0.001, OR 3.0, 95% CI 2.1-4.2 had the highest risk for ALF. Serum testosterone levels were significantly higher (P<0.001 at hepatitis flare point (8.2 ± 3.0 ng/mL than inactive phase (6.4 ± 2.0 ng/mL. CHB (8.30 ± 2.71 ng/mL, P = 7.6 × 10(-6 and ALF group (2.61 ± 1.83 ng/mL, P = 1.7 × 10(-17 had significantly different levels of testosterone in comparison with AsCs group (6.56 ± 2.36 ng/mL. The serum testosterone levels sharply decreased from hepatitis flare phase to liver failure phase, and tended to be normal at the recovery phase. Male AsCs with M-CAG alleles had significantly lower serum testosterone levels (P<0.05. CONCLUSIONS: There was a serum testosterone fluctuation during hepatitis B flare and HBV-related ALF, and the median CAG repeats in AR gene exon 1 were associated with lower serum testosterone levels in asymptomatic HBV carriers and an increased susceptibility to HBV-related ALF.

  7. CAG repeats determine brain atrophy in spinocerebellar ataxia 17: a VBM study.

    Kathrin Reetz

    Full Text Available BACKGROUND: Abnormal repeat length has been associated with an earlier age of onset and more severe disease progression in the rare neurodegenerative disorder spinocerebellar ataxia 17 (SCA17. METHODOLOGY/PRINCIPAL FINDINGS: To determine whether specific structural brain degeneration and rate of disease progression in SCA17 might be associated with the CAG repeat size, observer-independent voxel-based morphometry was applied to high-resolution magnetic resonance images of 16 patients with SCA17 and 16 age-matched healthy controls. The main finding contrasting SCA17 patients with healthy controls demonstrated atrophy in the cerebellum bilaterally. Multiple regression analyses with available genetic data and also post-hoc correlations revealed an inverse relationship again with cerebellar atrophy. Moreover, we found an inverse relationship between the CAG repeat length and rate of disease progression. CONCLUSIONS: Our results highlight the fundamental role of the cerebellum in this neurodegenerative disease and support the genotype-phenotype relationship in SCA17 patients. Genetic factors may determine individual susceptibility to neurodegeneration and rate of disease progression.

  8. Huntington CAG repeat size does not modify onset age in familial Parkinson’s disease: The GenePD Study

    McNicoll, Christopher F.; Latourelle, Jeanne C.; MacDonald, Marcy E.; Lew, Mark F.; Suchowersky, Oksana; Klein, Christine; Golbe, Lawrence I; Mark, Margery H; Growdon, John H.; Wooten, G. Frederick; Watts, Ray L.; Guttman, Mark; Racette, Brad A.; Perlmutter, Joel. S.; Ahmed, Anwar


    The ATP/ADP ratio reflects mitochondrial function and has been reported to be influenced by the size of the Huntington disease gene (HD) repeat. Impaired mitochondrial function has long been implicated in the pathogenesis of Parkinson’s disease (PD) and therefore, we evaluated the relationship of the HD CAG repeat size to PD onset age in a large sample of familial PD cases. PD affected siblings (n=495) with known onset ages from 248 families, were genotyped for the HD CAG repeat. Genotyping f...

  9. Huntington CAG repeat size does not modify onset age in familial Parkinson’s disease: The GenePD Study

    McNicoll, Christopher F.; Latourelle, Jeanne C.; MacDonald, Marcy E.; Lew, Mark F.; Suchowersky, Oksana; Klein, Christine; Golbe, Lawrence I.; Mark, Margery H.; Growdon, John H.; Wooten, G. Frederick; Watts, Ray L.; Guttman, Mark; Racette, Brad A.; Perlmutter, Joel S.; Ahmed, Anwar; Shill, Holly A.; Singer, Carlos; Saint-Hilaire, Marie H.; Massood, Tiffany; Huskey, Karen W.; DeStefano, Anita L.; Gillis, Tammy; Mysore, Jayalakshmi; Goldwurm, Stefano; Pezzoli, Gianni; Baker, Kenneth B.; Itin, Ilia; Litvan, Irene; Nicholson, Garth; Corbett, Alastair; Nance, Martha; Drasby, Edward; Isaacson, Stuart; Burn, David J.; Chinnery, Patrick F.; Pramstaller, Peter P.; Al-hinti, Jomana; Moller, Anette T.; Ostergaard, Karen; Sherman, Scott J.; Roxburgh, Richard; Snow, Barry; Slevin, John T.; Cambi, Franca; Gusella, James F.; Myers, Richard H.


    The ATP/ADP ratio reflects mitochondrial function and has been reported to be influenced by the size of the Huntington disease gene (HD) repeat. Impaired mitochondrial function has long been implicated in the pathogenesis of Parkinson’s disease (PD) and therefore, we evaluated the relationship of the HD CAG repeat size to PD onset age in a large sample of familial PD cases. PD affected siblings (n=495) with known onset ages from 248 families, were genotyped for the HD CAG repeat. Genotyping failed in 11 cases leaving 484 for analysis, including 35 LRRK2 carriers. All cases had HD CAG repeats (range 15 to 34) below the clinical range for HD, although 5.2 percent of the sample (n=25) had repeats in the intermediate range (the intermediate range lower limit=27; upper limit=35 repeats), suggesting that the prevalence of intermediate allele carriers in the general population is significant. No relation between the HD CAG repeat size and the age at onset for PD was found in this sample of familial PD. PMID:18649400

  10. Contributions of sex, testosterone, and androgen receptor CAG repeat number to virtual Morris water maze performance.

    Nowak, Nicole T; Diamond, Michael P; Land, Susan J; Moffat, Scott D


    The possibility that androgens contribute to the male advantage typically found on measures of spatial cognition has been investigated using a variety of approaches. To date, evidence to support the notion that androgens affect spatial cognition in healthy young adults is somewhat equivocal. The present study sought to clarify the association between testosterone (T) and spatial performance by extending measurements of androgenicity to include both measures of circulating T as well as an androgen receptor-specific genetic marker. The aims of this study were to assess the contributions of sex, T, and androgen receptor CAG repeat number (CAGr) on virtual Morris water task (vMWT) performance in a group of healthy young men and women. The hypothesis that men would outperform women on vMWT outcomes was supported. Results indicate that CAGr may interact with T to impact navigation performance and suggest that consideration of androgen receptor sensitivity is an important consideration in evaluating hormone-behavior relationships. PMID:24495604

  11. Mutant CAG repeats of Huntingtin transcript fold into hairpins, form nuclear foci and are targets for RNA interference

    de Mezer, Mateusz; Wojciechowska, Marzena; Napierala, Marek; Sobczak, Krzysztof; Krzyzosiak, Wlodzimierz J.


    The CAG repeat expansions that occur in translated regions of specific genes can cause human genetic disorders known as polyglutamine (poly-Q)-triggered diseases. Huntington’s disease and spinobulbar muscular atrophy (SBMA) are examples of these diseases in which underlying mutations are localized near other trinucleotide repeats in the huntingtin (HTT) and androgen receptor (AR) genes, respectively. Mutant proteins that contain expanded polyglutamine tracts are well-known triggers of pathoge...

  12. Effects of Anthocyanins on CAG Repeat Instability and Behaviour in Huntington’s Disease R6/1 Mice

    Møllersen, Linda; Moldestad, Olve; Rowe, Alexander D.; Bjølgerud, Anja; Holm, Ingunn; Tveterås, Linda; Klungland, Arne; Retterstøl, Lars


    Background: Huntington’s disease (HD) is a progressive neurodegenerative disorder caused by CAG repeat expansions in the HTT gene. Somatic repeat expansion in the R6/1 mouse model of HD depends on mismatch repair and is worsened by base excision repair initiated by the 7,8-dihydroxy-8-oxoguanine-DNA glycosylase (Ogg1) or Nei-like 1 (Neil1). Ogg1 and Neil1 repairs common oxidative lesions. Methods: We investigated whether anthocyanin antioxidants added daily to the drinking water could affect CAG repeat instability in several organs and behaviour in R6/1 HD mice. In addition, anthocyanin-treated and untreated R6/1 HD mice at 22 weeks of age were tested in the open field test and on the rotarod. Results: Anthocyanin-treated R6/1 HD mice showed reduced instability index in the ears and in the cortex compared to untreated R6/1 mice, and no difference in liver and kidney. There were no significant differences in any of the parameters tested in the behavioural tests among anthocyanin-treated and untreated R6/1 HD mice. Conclusions: Our results indicate that continuous anthocyanin-treatment may have modest effects on CAG repeat instability in the ears and the cortex of R6/1 mice. More studies are required to investigate if anthocyanin-treatment could affect behaviour earlier in the disease course. PMID:27540492

  13. Problems and solutions for the analysis of somatic CAG repeat expansion and their relationship to Huntington's disease toxicity

    Budworth, Helen; McMurray, Cynthia T.


    ABSTRACT Huntington's Disease is caused by inheritance of a single disease-length allele harboring an expanded CAG repeat, which continues to expand in somatic tissues with age. Whether somatic expansion contributed to toxicity was unknown. From extensive work from multiple laboratories, it has been made clear that toxicity depended on length of the inherited allele, but whether preventing or delaying somatic repeat expansion in vivo would be beneficial was unknown, since the inherited disease allele was still expressed. In Budworth et al., we provided definitive evidence that suppressing the somatic expansion in mice substantially delays disease onset in littermates that inherit the same disease-length allele. This key discovery opens the door for therapeutic approaches targeted at stopping or shortening the CAG tract during life. The analysis was difficult and, at times, non-standard. Here, we take the opportunity to discuss the challenges, the analytical solutions, and to address some controversial issues with respect to expansion biology.

  14. Undermasculinized genitalia in a boy with an abnormally expanded CAG repeat length in the androgen receptor gene.

    Ogata, T; Muroya, K; Ishii, T; Suzuki, Y; Nakada, T; Sasagawa, I


    We report an 11-year-old boy with undermasculinized genitalia and an abnormally expanded CAG repeat length at exon 1 of the androgen receptor (AR) gene. He had microphallus and scrotal hypospadias with chordee, and underwent urethroplasty at 4 years of age. At 11 years of age, a gonadotropin releasing hormone (GnRH) test yielded a relatively high leutinizing hormone (LH) response (0.7-->20.4 IU/l) and a relatively low follicle-stimulating hormone (FSH) response (1.7-->4.8 IU/l), and an human chorionic gonadotropin (hCG) test showed sufficient responses of testosterone (0.7-->23.0 nmol/l) and dihydrotestosterone (0.38-->2.95 nmol/l). The CAG repeat length was 44 for the boy and ranged from 12 to 32 for 100 control males. The DNA sequences of the AR gene were normal for the exons 1-8 and for the splice donor, splice acceptor and branch sites. The markedly expanded CAG repeat length appears to be relevant to the undermasculinized genitalia of this boy, because such an expandsion, which has previously been reported only in spinal and bulbar muscular atrophy, is known to reduce AR function. PMID:11422120

  15. Three Huntington's Disease Specific Mutation-Carrying Human Embryonic Stem Cell Lines Have Stable Number of CAG Repeats upon In Vitro Differentiation into Cardiomyocytes.

    Laureen Jacquet

    Full Text Available Huntington disease (HD; OMIM 143100, a progressive neurodegenerative disorder, is caused by an expanded trinucleotide CAG (polyQ motif in the HTT gene. Cardiovascular symptoms, often present in early stage HD patients, are, in general, ascribed to dysautonomia. However, cardio-specific expression of polyQ peptides caused pathological response in murine models, suggesting the presence of a nervous system-independent heart phenotype in HD patients. A positive correlation between the CAG repeat size and severity of symptoms observed in HD patients has also been observed in in vitro HD cellular models. Here, we test the suitability of human embryonic stem cell (hESC lines carrying HD-specific mutation as in vitro models for understanding molecular mechanisms of cardiac pathology seen in HD patients. We have differentiated three HD-hESC lines into cardiomyocytes and investigated CAG stability up to 60 days after starting differentiation. To assess CAG stability in other tissues, the lines were also subjected to in vivo differentiation into teratomas for 10 weeks. Neither directed differentiation into cardiomyocytes in vitro nor in vivo differentiation into teratomas, rich in immature neuronal tissue, led to an increase in the number of CAG repeats. Although the CAG stability might be cell line-dependent, induced pluripotent stem cells generated from patients with larger numbers of CAG repeats could have an advantage as a research tool for understanding cardiac symptoms of HD patients.

  16. Androgen Receptor Repeat Length Polymorphism Associated with Male-to-Female Transsexualism

    Hare, Lauren; Bernard, Pascal; Sánchez, Francisco J.; Baird, Paul N.; Vilain, Eric; Kennedy, Trudy; Harley, Vincent R.


    Background There is a likely genetic component to transsexualism, and genes involved in sex steroidogenesis are good candidates. We explored the specific hypothesis that male-to-female transsexualism is associated with gene variants responsible for undermasculinization and/or feminization. Specifically, we assessed the role of disease-associated repeat length polymorphisms in the androgen receptor (AR), estrogen receptor β (ERβ), and aromatase (CYP19) genes. Methods Subject-control analysis included 112 male-to-female transsexuals and 258 non-transsexual males. Associations and interactions were investigated between CAG repeat length in the AR gene, CA repeat length in the ERβ gene, and TTTA repeat length in the CYP19 gene and male-to-female transsexualism. Results A significant association was identified between transsexualism and the AR allele, with transsexuals having longer AR repeat lengths than non-transsexual male control subjects (p = .04). No associations for transsexualism were evident in repeat lengths for CYP19 or ERβ genes. Individuals were then classified as short or long for each gene polymorphism on the basis of control median polymorphism lengths in order to further elucidate possible combined effects. No interaction associations between the three genes and transsexualism were identified. Conclusions This study provides evidence that male gender identity might be partly mediated through the androgen receptor. PMID:18962445

  17. Presence of terminal EPIYA phosphorylation motifs in Helicobacter pylori CagA contributes to IL-8 secretion, irrespective of the number of repeats.

    Konstantinos S Papadakos

    Full Text Available CagA protein contributes to pro-inflammatory responses during H. pylori infection, following its intracellular delivery to gastric epithelial cells. Here, we report for the first time in an isogenic background, on the subtle role of CagA phosphorylation on terminal EPIYA-C motifs in the transcriptional activation and expression of IL-8. We utilized isogenic H. pylori mutants of P12 reference strain, expressing CagA with varying number of EPIYA-C motifs and the corresponding phosphorylation defective EPIFA-C motifs while preserving intact the CM multimerization motifs. These mutants had been previously closely scrutinized in terms of type IV secretion system functionality, CagA translocation and its subsequent phosphorylation. Following infection of gastric epithelial cell lines, transcriptional activation of IL-8 gene and secreted IL-8 levels were found to be strictly dependent upon the functionality of the EPIYA-C phosphorylation motifs, as EPIFA-C phosphorylation-deficient CagA expression failed to induce full IL-8 transcriptional activity. Interestingly, levels of IL-8 gene activation and of secreted IL-8 were the same, irrespective of the number of EPIYA-C terminal repeats. We monitored IkBα phosphorylation and confirmed CagA involvement in NF-kB activation. Furthermore, we observed that presence of EPIYA-C functional phosphorylation motifs contributed to NF-kB activation. NF-kB upstream signaling events, such as early ERK1/2 and AKT activation were confirmed to be independent of EPIYA-C phosphorylation. On the contrary, use of TAK1 specific inhibitor 5Z-7-Oxozeaenol resulted in complete arrest of IL-8 secretion, in a dose-dependent manner, irrespective of CagA status. H. pylori-infected TAK1(-/- mouse embryonic fibroblasts (MEFs failed to induce NF-kB activity, unlike the respective control MEFs. CagA and TAK1 were found to immunoprecipitate together, irrespective of CagA EPIYA-C status, thus confirming earlier reports of TAK1 and Cag

  18. The Presence of Clitoromegaly in the Nonclassical Form of 21-Hydroxylase Deficiency Could Be Partially Modulated by the CAG Polymorphic Tract of the Androgen Receptor Gene

    Garcia Gomes, Larissa; Bugano Diniz Gomes, Diogo; Marcondes, José Antônio Miguel; Madureira, Guiomar; de Mendonca, Berenice Bilharinho; Bachega, Tânia A. Sartori Sanchez


    Background In the nonclassical form (NC), good correlation has been observed between genotypes and 17OH-progesterone (17-OHP) levels. However, this correlation was not identified with regard to the severity of hyperandrogenic manifestations, which could depend on interindividual variability in peripheral androgen sensitivity. Androgen action is modulated by the polymorphic CAG tract (nCAG) of the androgen receptor (AR) gene and by polymorphisms in 5α-reductase type 2 (SRD5A2) enzyme, both of which are involved in the severity of hyperandrogenic disorders. Objectives To analyze whether nCAG-AR and SRD5A2 polymorphisms influence the severity of the nonclassical phenotype. Patients NC patients (n = 114) diagnosed by stimulated-17OHP ≥10 ng/mL were divided into groups according to the beginning of hyperandrogenic manifestations (pediatric and adolescent/adult) and CYP21A2 genotypes (C/C: homozygosis for mild mutations; A/C: compound heterozygosis for severe/mild mutations). Methods CYP21A2 mutations were screened by allelic-specific PCR, MLPA and/or sequencing. HpaII-digested and HpaII-undigested DNA samples underwent GeneScan analysis to study nCAG, and the SRD5A2 polymorphisms were screened by RLFP. Results Mean nCAG did not differ among pediatric, adolescent/adult and asymptomatic subjects. In the C/C genotype, we observed a significantly lower frequency of longer CAG alleles in pediatric patients than in adolescent/adults (p = 0.01). In patients carrying the A/C genotype, the frequencies of shorter and longer CAG alleles did not differ between pediatric patients and adolescent/adults (p>0.05). Patients with clitoromegaly had significantly lower weighted CAG biallelic mean than those without it: 19.1±2.7 and 21.6±2.5, respectively (p = 0.007), independent of the CYP21A2 genotype's severity. The SRD5A2 polymorphisms were not associated with the variability of hyperandrogenic NC phenotypes. Conclusions In this series, we observed a modulatory effect of the CAG

  19. Bovine proteins containing poly-glutamine repeats are often polymorphic and enriched for components of transcriptional regulatory complexes

    Whan, Vicki


    Abstract Background About forty human diseases are caused by repeat instability mutations. A distinct subset of these diseases is the result of extreme expansions of polymorphic trinucleotide repeats; typically CAG repeats encoding poly-glutamine (poly-Q) tracts in proteins. Polymorphic repeat length variation is also apparent in human poly-Q encoding genes from normal individuals. As these coding sequence repeats are subject to selection in mammals, it has been suggested that normal variations in some of these typically highly conserved genes are implicated in morphological differences between species and phenotypic variations within species. At present, poly-Q encoding genes in non-human mammalian species are poorly documented, as are their functions and propensities for polymorphic variation. Results The current investigation identified 178 bovine poly-Q encoding genes (Q ≥ 5) and within this group, 26 genes with orthologs in both human and mouse that did not contain poly-Q repeats. The bovine poly-Q encoding genes typically had ubiquitous expression patterns although there was bias towards expression in epithelia, brain and testes. They were also characterised by unusually large sizes. Analysis of gene ontology terms revealed that the encoded proteins were strongly enriched for functions associated with transcriptional regulation and many contributed to physical interaction networks in the nucleus where they presumably act cooperatively in transcriptional regulatory complexes. In addition, the coding sequence CAG repeats in some bovine genes impacted mRNA splicing thereby generating unusual transcriptional diversity, which in at least one instance was tissue-specific. The poly-Q encoding genes were prioritised using multiple criteria for their likelihood of being polymorphic and then the highest ranking group was experimentally tested for polymorphic variation within a cattle diversity panel. Extensive and meiotically stable variation was identified

  20. A specific A/T polymorphism in Western tyrosine phosphorylation B-motifs regulates Helicobacter pylori CagA epithelial cell interactions.

    Xue-Song Zhang


    Full Text Available Helicobacter pylori persistently colonizes the human stomach, with mixed roles in human health. The CagA protein, a key host-interaction factor, is translocated by a type IV secretion system into host epithelial cells, where its EPIYA tyrosine phosphorylation motifs (TPMs are recognized by host cell kinases, leading to multiple host cell signaling cascades. The CagA TPMs have been described as type A, B, C or D, each with a specific conserved amino acid sequence surrounding EPIYA. Database searching revealed strong non-random distribution of the B-motifs (including EPIYA and EPIYT in Western H. pylori isolates. In silico analysis of Western H. pylori CagA sequences provided evidence that the EPIYT B-TPMs are significantly less associated with gastric cancer than the EPIYA B-TPMs. By generating and using a phosphorylated CagA B-TPM-specific antibody, we demonstrated the phosphorylated state of the CagA B-TPM EPIYT during H. pylori co-culture with host cells. We also showed that within host cells, CagA interaction with phosphoinositol 3-kinase (PI3-kinase was B-TPM tyrosine-phosphorylation-dependent, and the recombinant CagA with EPIYT B-TPM had higher affinity to PI3-kinase and enhanced induction of AKT than the isogenic CagA with EPIYA B-TPM. Structural modeling of the CagA B-TPM motif bound to PI3-kinase indicated that the threonine residue at the pY+1 position forms a side-chain hydrogen bond to N-417 of PI3-kinase, which cannot be formed by alanine. During co-culture with AGS cells, an H. pylori strain with a CagA EPIYT B-TPM had significantly attenuated induction of interleukin-8 and hummingbird phenotype, compared to the isogenic strain with B-TPM EPIYA. These results suggest that the A/T polymorphisms could regulate CagA activity through interfering with host signaling pathways related to carcinogenesis, thus influencing cancer risk.

  1. Random rapid amplification of cDNA ends (RRACE) allows for cloning of multiple novel human cDNA fragments containing (CAG)n repeats.

    Carney, J P; McKnight, C; VanEpps, S; Kelley, M R


    We describe a new technique for isolating cDNA fragments in which (i) either a partial sequence of the cDNA is known or (ii) a repeat sequence is utilized. We have used this technique, termed random rapid amplification of cDNA ends (random RACE), to isolate a number of trinucleotide repeat (CAG)n-containing genes. Using the random RACE (RRACE) technique, we have isolated over a hundred (CAG)n-containing genes. The results of our initial analysis of ten clones indicate that three are identical to previously cloned (CAG)n-containing genes. Three of our clones matched with expressed sequence tags, one of which contained a CA repeat. The remaining four clones did not match with any sequence in GenBank. These results indicate that this approach provides a rapid and efficient method for isolating trinucleotide repeat-containing cDNA fragments. Finally, this technique may be used for purposes other than cloning repeat-containing cDNA fragments. If only a partial sequence of a gene is known, our system, described here, provides a rapid and efficient method for isolating a fragment of the gene of interest. PMID:7536696

  2. Novel BAC mouse model of Huntington’s disease with 225 CAG repeats exhibits an early widespread and stable degenerative phenotype

    Wegrzynowicz, Michal; Bichell, Terry Jo; Soares, Barbara D.; Loth, Meredith K.; McGlothan, Jennifer L.; Alikhan, Fatima S.; Hua, Kegang; Coughlin, Jennifer M.; Holt, Hunter K.; Jetter, Christopher S.; Mori, Susumu; Pomper, Martin G.; Osmand, Alexander P.; Guilarte, Tomás R.; Bowman, Aaron B.


    BACKGROUND Unusually large CAG repeat expansions (>60) in exon one of Huntingtin (HTT) are invariably associated with a juvenile-onset form of Huntington’s disease (HD), characterized by a more extensive and rapidly progressing neuropathology than the more prevalent adult-onset form. However, existing mouse models of HD that express the full-length Htt gene with CAG repeat lengths associated with juvenile HD (ranging between ~75 to ~150 repeats in published models) exhibit selective neurodegenerative phenotypes more consistent with adult-onset HD. OBJECTIVE To determine if a very large CAG repeat (>200) in full-length Htt elicits neurodegenerative phenotypes consistent with juvenile HD. METHODS Using a bacterial artificial chromosome (BAC) system, we generated mice expressing full-length mouse Htt with ~225 CAG repeats under control of the mouse Htt promoter. Mice were characterized using behavioral, neuropathological, biochemical and brain imaging methods. RESULTS BAC-225Q mice exhibit phenotypes consistent with a subset of features seen in juvenile-onset HD: very early motor behavior abnormalities, reduced body weight, widespread and progressive increase in Htt aggregates, gliosis, and neurodegeneration. Early striatal pathology was observed, including reactive gliosis and loss of dopamine receptors, prior to detectable volume loss. HD-related blood markers of impaired energy metabolism and systemic inflammation were also increased. Aside from an age-dependent progression of diffuse nuclear aggregates at 6 months of age to abundant neuropil aggregates at 12 months of age, other pathological and motor phenotypes showed little to no progression. CONCLUSIONS The HD phenotypes present in animals 3 to 12 months of age make the BAC-225Q mice a unique and stable model of full-length mutant Htt associated phenotypes, including body weight loss, behavioral impairment and HD-like neurodegenerative phenotypes characteristic of juvenile-onset HD and/or late-stage adult

  3. Multiple repeats of Helicobacter pylori CagA EPIYA-C phosphorylation sites predict risk of gastric ulcer in Iran.

    Honarmand-Jahromy, Sahar; Siavoshi, Farideh; Malekzadeh, Reza; Sattari, Taher Nejad; Latifi-Navid, Saeid


    Biological activity of Helicobacter pylori oncoprotein CagA is determined by a diversity in the tyrosine phosphorylation motif sites. In the present study, the diversity and the type of the H. pylori CagA EPIYA motifs and their association with gastric ulcer (GU) and duodenal ulcer (DU) in Iranian dyspeptic patients were assessed. PCR amplification, sequencing, and bioinformatic analysis were performed to determine the pattern of CagA EPIYA motifs. Of 168 H. pylori cagA(+) strains, the frequency of ABC was 93.50%, ABCCC 5.40%, ABC + ABCCC 0.6% and ABCC 0.6%. There was no EPIYA-D segment. The ABCCC pattern of EPIYA motif was more frequent in the H. pylori isolates from GU (8/50, 16%) than in those from chronic gastritis (CG) (0/81, 0%) (P = 0). In contrast, The ABC pattern of EPIYA motif was less frequent in the H. pylori isolates from GU (41/50, 82%) than in those from CG (80/81, 98.80%) (Age-sex-adjusted odds ratio (OR) = 0.020, 95% CI = 0.002-0.259; P = 0.003). The distribution of the ABC motif was almost the same in H. pylori isolates from CG (98.80%) and DU diseases (97.30%). There was no significant association between the number of CagA EPIYA-C segment and DU (P > 0.05). We have proposed that CagA from Iranian H. pylori strains were Western type and all strains had active phosphorylation sites. The three EPIYA-C motifs of CagA were more frequently observed in the H. pylori strains from GU; thus it might be an important biomarker for predicting the GU risk in Iran. PMID:26408373

  4. Marked phenotypic heterogeneity associated with expansion of a CAG repeat sequence at the spinocerebellar ataxia 3/Machado-Joseph disease locus

    Cancel, G.; Abbas, N.; Stevanin, G. [Hopital de la Salpetriere, Paris (France)] [and others


    The spinocerebellar ataxia 3 locus (SCA3) for type I autosomal dominant cerebellar ataxia (ADCA type I), a clinically and genetically heterogeneous group of neurodegenerative disorders, has been mapped to chromosome 14q32.1. ADCA type I patients from families segregating SCA3 share clinical features in common with those with Machado-Joseph disease (MJD), the gene of which maps to the same region. We show here that the disease gene segregating in each of three French ADCA type I kindreds and in a French family with neuropathological findings suggesting the ataxochoreic form of dentatorubropallidoluysian atrophy carries an expanded CAG repeat sequence located at the same locus as that for MJD. Analysis of the mutation in these families shows a strong negative correlation between size of the expanded CAG repeat and age at onset of clinical disease. Instability of the expanded triplet repeat was not found to be affected by sex of the parent transmitting the mutation. Evidence was found for somatic and gonadal mosaicism for alleles carrying expanded trinucleotide repeats. 36 refs., 5 figs., 2 tabs.

  5. 家族性亨廷顿病临床和(CAG)n多态性分析%The polymorphism analysis of (CAG)n gene in Huntington's disease

    初海鹰; 王剑锋; 杨佩满; 黄尚志


    @@ 亨廷顿病(Huntington's disease, HD)是一种常染色体显性遗传的基底节和大脑皮层变性疾病,临床特征为慢性进行性的舞蹈样动作和痴呆.1993年,分离获得HD相关基因IT15,并确定其开放阅读框架5'端多态性CAG三核苷酸重复序列的过度扩展为致病的突变[1],正常人群(CAG)n拷贝数为11-34个.通过检测CAG拷贝数,可从基因水平确诊HD.基于此,我们对一个家族性HD家系两个病例进行了基因分析.

  6. ATXN2 with intermediate-length CAG/CAA repeats does not seem to be a risk factor in hereditary spastic paraplegia

    Nielsen, Troels Tolstrup; Svenstrup, Kirsten; Budtz-Jørgensen, Esben;


    degeneration with motor neuron disease (FTD-MND), since TDP-43 positive inclusions have recently been found in an HSP subtype, and TDP-43 are found in abundance in pathological inclusions of both ALS and FTD-MND. Furthermore, ataxin-2 (encoded by the gene ATXN2), a polyglutamine containing protein elongated in...... spinocerebellar ataxia type 2, has been shown to be a modulator of TDP-43 induced toxicity in ALS animal and cell models. Finally, it has been shown that ATXN2 with non-pathogenic intermediate-length CAG/CAA repeat elongations (encoding the polyglutamine tract) is a genetic risk factor of ALS. Considering the...

  7. Distribution of Polymorphic and Non-Polymorphic Microsatellite Repeats in Xenopus tropicalis

    Amy K. Sater


    Full Text Available The results of our bioinformatics analysis have found over 91,000 di-, tri-, and tetranucleotide microsatellites in our survey of 25% of the X. tropicalis genome, suggesting there may be over 360,000 within the entire genome. Within the X. tropicalis genome, dinucleotide (78.7% microsatellites vastly out numbered tri- and tetranucleotide microsatellites. Similarly, AT-rich repeats are overwhelmingly dominant. The four AT-only motifs (AT, AAT, AAAT, and AATT account for 51,858 out of 91,304 microsatellites found. Individually, AT microsatellites were the most common repeat found, representing over half of all di-, tri-, and tetranucleotide microsatellites. This contrasts with data from other studies, which show that AC is the most frequent microsatellite in vertebrate genomes (Toth et al. 2000. In addition, we have determined the rate of polymorphism for 5,128 non-redundant microsatellites, embedded in unique sequences. Interestingly, this subgroup of microsatellites was determined to have significantly longer repeats than genomic microsatellites as a whole. In addition, microsatellite loci with tandem repeat lengths more than 30 bp exhibited a significantly higher degree of polymorphism than other loci. Pairwise comparisons show that tetranucleotide microsatellites have the highest polymorphic rates. In addition, AAT and ATC showed significant higher polymorphism than other trinucleotide microsatellites, while AGAT and AAAG were significantly more polymorphic than other tetranucleotide microsatellites.

  8. Modelling studies on neurodegenerative disease-causing triplet repeat sequences d(GGC/GCC)n and d(CAG/CTG)n

    Shibasish Chowdhury; Manju Bansal


    Model building and molecular mechanics studies have been carried out to examine the potential structures for d(GGC/GCC)5 and d(CAG/CTG)5 that might relate to their biological function and association with triplet repeat expansion diseases. Model building studies suggested that hairpin and quadruplex structures could be formed with these repeat sequences. Molecular mechanics studies have demonstrated that the hairpin and hairpin dimer structures of triplet repeat sequences formed by looping out of the two strands are as favourable as the corresponding B-DNA type hetero duplex structures. Further, at high salt condition, Greek key type quadruplex structures are energetically comparable with hairpin dimer and B-DNA type duplex structures. All tetrads in the quadruplex structures are well stacked and provide favourable stacking energy values. Interestingly, in the energy minimized hairpin dimer and Greek key type quadruplex structures, all the bases even in the non-G tetrads are cyclically hydrogen bonded, even though the A, C and T-tetrads were not hydrogen bonded in the starting structures.

  9. Neil1 is a genetic modifier of somatic and germline CAG trinucleotide repeat instability in R6/1 mice

    Møllersen, Linda; Rowe, Alexander D; Illuzzi, Jennifer L.; Hildrestrand, Gunn A; Gerhold, Katharina J.; Tveterås, Linda; Bjølgerud, Anja; Wilson, David M.; Bjørås, Magnar; Klungland, Arne


    Huntington's disease (HD) is a progressive neurodegenerative disorder caused by trinucleotide repeat (TNR) expansions. We show here that somatic TNR expansions are significantly reduced in several organs of R6/1 mice lacking exon 2 of Nei-like 1 (Neil1) (R6/1/Neil1 −/−), when compared with R6/1/Neil1 +/+ mice. Somatic TNR expansion is measured by two different methods, namely mean repeat change and instability index. Reduced somatic expansions are more pronounced in male R6/1/Neil1 −/− mice, ...

  10. Intermediate CAG repeat lengths (53,54) for MJD/SCA3 are associated with an abnormal phenotype

    van Alfen, N; Sinke, R J; Zwarts, M J; Gabreëls-Festen, A; Praamstra, P; Kremer, B P; Horstink, M W


    We report on a Dutch family in which 4 members in 2 generations have intermediate repeat lengths (53 and 54) for Machado-Joseph Disease/Spinocerebellar Ataxia (MJD/SCA3). All but the youngest have a restless legs syndrome with fasciculations and a sensorimotor axonal polyneuropathy. Central neurolog

  11. Simple sequence repeat length polymorphisms mapped to rat chromosome 11.

    Du, Y; Remmers, E F; Goldmuntz, E A; Zha, H; Mathern, P; Crofford, L J; Wilder, R L


    Two genes and two anonymous DNA loci were mapped to rat chromosome 11 using F2 intercross progeny of Fischer (F344/N) and Lewis (LEW/N) inbred rats. These four loci formed a single linkage group covering 21.5 cM with the following map order: somatostatin (SST)-D11N161-D11N18-cell surface protein (MOX2). These four loci were typed by PCR-based simple sequence repeat (SSR) length polymorphism detection. For each marker four to seven different alleles were detected using a panel of 13 inbred rat strains (F344/N, LEW/N, BN/SsN, BUF/N, LER/N, MR/N, MNR/N, LOU/MN, ACI/N, WBB1/N, WBB2/N, SHR/N, WKY/N). Comparative gene mapping analysis suggests syntenic conservation between rat chromosome 11 and mouse Chromosome 16. PMID:8222758

  12. Unexpanded and intermediate CAG polymorphisms at the SCA2 locus (ATXN2) in the Cuban population: evidence about the origin of expanded SCA2 alleles

    Laffita-Mesa, José Miguel; Velázquez-Pérez, Luis C; Santos Falcón, Nieves; Cruz-Mariño, Tania; González Zaldívar, Yanetza; Vázquez Mojena, Yaimee; Almaguer-Gotay, Dennis; Almaguer Mederos, Luis Enrique; Rodríguez Labrada, Roberto


    The role of short, large or intermediate normal alleles (ANs) of the ataxin-2 gene in generating expanded alleles (EAs) causing spinocerebellar ataxia type 2 (SCA2) is poorly understood. It has been postulated that SCA2 prevalence is related to the frequency of large ANs. SCA2 shows the highest worldwide prevalence in Cuban population, which is therefore a unique source for studying the relationship between the frequency of large and intermediate alleles and the frequency of SCA2 mutation. Through genetic polymorphism analyses in a comprehensive sample (∼3000 chromosomes), we show that the frequency of large ANs in the ataxin-2 gene is the highest worldwide, although short ANs are also frequent. This highly polymorphic population displayed also high variability in the CAG sequence, featured by loss of the anchor CAA interruption(s). In addition, large ANs showed germinal and somatic instability. Our study also includes related genotypic, genealogical and haplotypic data and provides substantial evidence with regard to the role of large and intermediate alleles in the generation of pathological EAs. PMID:21934711

  13. Presence of terminal EPIYA phosphorylation motifs in Helicobacter pylori CagA contributes to IL-8 secretion, irrespective of the number of repeats.

    Papadakos, Konstantinos S.; Sougleri, Ioanna S; Mentis, Andreas F; Efstathios Hatziloukas; Sgouras, Dionyssios N.


    CagA protein contributes to pro-inflammatory responses during H. pylori infection, following its intracellular delivery to gastric epithelial cells. Here, we report for the first time in an isogenic background, on the subtle role of CagA phosphorylation on terminal EPIYA-C motifs in the transcriptional activation and expression of IL-8. We utilized isogenic H. pylori mutants of P12 reference strain, expressing CagA with varying number of EPIYA-C motifs and the corresponding phosphorylation de...

  14. Oxidized dNTPs and the OGG1 and MUTYH DNA glycosylases combine to induce CAG/CTG repeat instability.

    Cilli, Piera; Ventura, Ilenia; Minoprio, Anna; Meccia, Ettore; Martire, Alberto; Wilson, Samuel H; Bignami, Margherita; Mazzei, Filomena


    DNA trinucleotide repeat (TNR) expansion underlies several neurodegenerative disorders including Huntington's disease (HD). Accumulation of oxidized DNA bases and their inefficient processing by base excision repair (BER) are among the factors suggested to contribute to TNR expansion. In this study, we have examined whether oxidation of the purine dNTPs in the dNTP pool provides a source of DNA damage that promotes TNR expansion. We demonstrate that during BER of 8-oxoguanine (8-oxodG) in TNR sequences, DNA polymerase β (POL β) can incorporate 8-oxodGMP with the formation of 8-oxodG:C and 8-oxodG:A mispairs. Their processing by the OGG1 and MUTYH DNA glycosylases generates closely spaced incisions on opposite DNA strands that are permissive for TNR expansion. Evidence in HD model R6/2 mice indicates that these DNA glycosylases are present in brain areas affected by neurodegeneration. Consistent with prevailing oxidative stress, the same brain areas contained increased DNA 8-oxodG levels and expression of the p53-inducible ribonucleotide reductase. Our in vitro and in vivo data support a model where an oxidized dNTPs pool together with aberrant BER processing contribute to TNR expansion in non-replicating cells. PMID:26980281

  15. Polymorphic repeat in AIB1 does not alter breast cancer risk

    We assessed the association between a glutamine repeat polymorphism in AIB1 and breast cancer risk in a case-control study (464 cases, 624 controls) nested within the Nurses' Health Study cohort. We observed no association between AIB1 genotype and breast cancer incidence, or specific tumor characteristics. These findings suggest that AIB1 repeat genotype does not influence postmenopausal breast cancer risk among Caucasian women in the general population. A causal association between endogenous and exogenous estrogens and breast cancer has been established. Steroid hormones regulate the expression of proteins that are involved in breast cell proliferation and development after binding to their respective steroid hormone receptors. Coactivator and corepressor proteins have recently been identified that interact with steroid hormone receptors and modulate transcriptional activation [1]. AIB1 (amplified in breast 1) is a member of the steroid receptor coactivator (SRC) family that interacts with estrogen receptor (ER)α in a ligand-dependent manner, and increases estrogen-dependent transcription [2]. Amplification and overexpression of AIB1 has been observed in breast and ovarian cancer cell lines and in breast tumors [2,3]. A polymorphic stretch of glutamine amino acids, with unknown biologic function, has recently been described in the carboxyl-terminal region of AIB1 [4]. Among women with germline BRCA1 mutations, significant positive associations were observed between AIB1 alleles with 26 or fewer glutamine repeats and breast cancer risk [5] To establish whether AIB1 repeat alleles are associated with breast cancer risk and specific tumor characteristics among Caucasian women. We evaluated associations prospectively between AIB1 alleles and breast cancer risk in the Nurses' Health Study using a nested case-control design. The Nurses' Health Study was initiated in 1976, when 121 700 US-registered nurses between the ages of 30 and 55 years returned an

  16. Severe and rapidly progressing cognitive phenotype in a SCA17-family with only marginally expanded CAG/CAA repeats in the TATA-box binding protein gene: A case report

    Nielsen Troels


    Full Text Available Abstract Background The autosomal dominant spinocerebellar ataxias (SCAs confine a group of rare and heterogeneous disorders, which present with progressive ataxia and numerous other features e.g. peripheral neuropathy, macular degeneration and cognitive impairment, and a subset of these disorders is caused by CAG-repeat expansions in their respective genes. The diagnosing of the SCAs is often difficult due to the phenotypic overlap among several of the subtypes and with other neurodegenerative disorders e.g. Huntington’s disease. Case presentation We report a family in which the proband had rapidly progressing cognitive decline and only subtle cerebellar symptoms from age 42. Sequencing of the TATA-box binding protein gene revealed a modest elongation of the CAG/CAA-repeat of only two repeats above the non-pathogenic threshold of 41, confirming a diagnosis of SCA17. Normally, repeats within this range show reduced penetrance and result in a milder disease course with slower progression and later age of onset. Thus, this case presented with an unusual phenotype. Conclusions The current case highlights the diagnostic challenge of neurodegenerative disorders and the need for a thorough clinical and paraclinical examination of patients presenting with rapid cognitive decline to make a precise diagnosis on which further genetic counseling and initiation of treatment modalities can be based.

  17. Androgen Receptor Gene Polymorphism, Aggression, and Reproduction in Tanzanian Foragers and Pastoralists

    Butovskaya, Marina L.; Lazebny, Oleg E.; Vasilyev, Vasiliy A.; Dronova, Daria A.; Karelin, Dmitri V.; Mabulla, Audax Z. P.; Shibalev, Dmitri V.; Shackelford, Todd K.; Fink, Bernhard; Ryskov, Alexey P.


    The androgen receptor (AR) gene polymorphism in humans is linked to aggression and may also be linked to reproduction. Here we report associations between AR gene polymorphism and aggression and reproduction in two small-scale societies in northern Tanzania (Africa)—the Hadza (monogamous foragers) and the Datoga (polygynous pastoralists). We secured self-reports of aggression and assessed genetic polymorphism of the number of CAG repeats for the AR gene for 210 Hadza men and 229 Datoga men (aged 17–70 years). We conducted structural equation modeling to identify links between AR gene polymorphism, aggression, and number of children born, and included age and ethnicity as covariates. Fewer AR CAG repeats predicted greater aggression, and Datoga men reported more aggression than did Hadza men. In addition, aggression mediated the identified negative relationship between CAG repeats and number of children born. PMID:26291982

  18. A Specific A/T Polymorphism in Western Tyrosine Phosphorylation B-Motifs Regulates Helicobacter pylori CagA Epithelial Cell Interactions

    Zhang, Xue-Song; Tegtmeyer, Nicole; Traube, Leah; Jindal, Shawn; Perez-Perez, Guillermo; Sticht, Heinrich; Backert, Steffen; Blaser, Martin J


    Abstract Helicobacter pylori persistently colonizes the human stomach, with mixed roles in human health. The CagA protein, a key host-interaction factor, is translocated by a type IV secretion system into host epithelial cells, where its EPIYA tyrosine phosphorylation motifs (TPMs) are recognized by host cell kinases, leading to multiple host cell signaling cascades. The CagA TPMs have been described as type A, B, C or D, each with a specific conserved amino acid sequence surrounding EPIYA...

  19. Comparative Nucleotide Sequence Analysis of Polymorphic Variable-Number Tandem-Repeat Loci in Mycobacterium ulcerans

    Ablordey, A; Hilty, M.; Stragier, Pieter; Swings, Jean; Portaels, F.


    We analyzed a set of variable-number tandem-repeat (VNTR) loci to assess their nucleotide sequence diversity in isolates of three Mycobacterium ulcerans genotypes. Sequence variants in two loci resulted in intraspecies resolution of Southeast Asian and Asian genotypes in contrast to a homogenous sequence composition among African isolates. Nucleotide sequence polymorphism in repeat units can enhance discrimination of VNTR loci.

  20. Progress study on the mechanism of CAG repeats dynamic mutation in polyQ disease%多聚谷氨酰胺病CAG重复序列动态突变机制研究进展

    王春荣; 江泓


    多聚谷氨酰胺病是一类中枢神经系统退行性疾病.由致病基因外显子内胞嘧啶-腺嘌呤-鸟嘌呤(CAG)三核苷酸重复序列拷贝数异常扩增导致其编码的多聚谷氨酰胺链异常延长,引起多聚谷氨酰胺扩展突变蛋白积聚而致病.迄今为止,共发现9种因多聚谷氨酰胺扩展突变型蛋白积聚引起的遗传性神经退行性疾病.CAG重复序列在代间传递过程中发生动态突变(拷贝数不断扩增),进而导致发病年龄提前和疾病严重程度增加.%Polyglutamine (polyQ) disease is a group of neurodegenerative disorders caused by abnormal expansion of CAG repeats within coding regions of certain causative genes, which are translated into a series of abnormally expanded polyQ tracts causing cytotoxicity. So far, nine diseases caused by expanded polyQ tracts have been demonstrated including Huntington's disease (HD), spinobulbar muscular atrophy (SBMA), dentatorubral-pallidoluysian atrophy (DRPLA) and several spinocerebellar ataxias subtypes (SCA). In human, long CAG repeats tend to expand during transmissions from parent to offspring, named as dynamic mutation, leading to an earlier age of disease onset and more severe symptoms in subsequent generations. The review presents some novel mechanisms based on dynamic mutation.

  1. Clinical characteristics of Huntington disease in two pedigrees and analysis of expanded CAG trinucleotide repeat%2个Huntington病家系临床特征及CAG重复性分析

    曹广娜; 包新华; 卢红梅; 张晶晶; 马一楠; 顾卫红; 熊晖; 秦炯; 吴希如


    目的:探讨Huntington病(Huntington disease,HD)的临床和遗传特征.方法:对收集的2个中国汉族HD家系患者的临床资料进行综合分析,应用聚合酶链式反应及基因扫描方法对其中9例家系成员的IT15基因的三核苷酸重复序列进行分析.结果:在两个家系中确诊了6例患者(男女均有发病),患者IT15基因的基因型均为杂合子,致病CAG重复拷贝数介于40~78次.两个家系中子代较父代发病年龄提前,家系2中可见发病年龄与CAG重复拷贝数呈负相关.6例患者中有1例为少年型HD,其临床表现明显不同于成人型,以肌张力障碍为主要表现.结论:HD是一种由CAG重复序列异常扩增所致的神经变性病,存在遗传早现现象;少年型HD的临床表现不同于成人型,CAG重复拷贝数与发病年龄及疾病严重程度有关.%Objective: To understand the clinical and genetic features of Huntington disease ( HD) . Methods: The clinical data of HD cases from 2 Chinese families were analyzed and trinucleotide repeat in the IT15 gene were investigated in 9 of the two families by polymerase chain reaction and GeneScan. Results : Among the two pedigrees, 6 cases were ascertained as HD by genetic test. Genotypes of IT15 were heterozygous in these HD patients. CAG repeat of the patients in the HD chromosome were 40 -78. In the two pedigrees, the onset age was earlier in the subsequent generations than that of their fathers. In pedigree 2, the onset age was inversely correlated with CAG repeat number. One out of the 6 cases was juvenile-onset type of Huntington disease, whose clinical symptoms were different from those of the adultonset cases, especially the hypertonic manifestation. Conclusion: HD is an autosomal dominant neurodegenerative disorder with genetic anticipation caused by enlargement of CAG repeat in IT15 gene. The clinical manifestation is different between the juvenile-onset and the adult-onset. The number of CAG repeat is inversely

  2. Characterization and compilation of polymorphic simple sequence repeat (SSR markers of peanut from public database

    Zhao Yongli


    Full Text Available Abstract Background There are several reports describing thousands of SSR markers in the peanut (Arachis hypogaea L. genome. There is a need to integrate various research reports of peanut DNA polymorphism into a single platform. Further, because of lack of uniformity in the labeling of these markers across the publications, there is some confusion on the identities of many markers. We describe below an effort to develop a central comprehensive database of polymorphic SSR markers in peanut. Findings We compiled 1,343 SSR markers as detecting polymorphism (14.5% within a total of 9,274 markers. Amongst all polymorphic SSRs examined, we found that AG motif (36.5% was the most abundant followed by AAG (12.1%, AAT (10.9%, and AT (10.3%.The mean length of SSR repeats in dinucleotide SSRs was significantly longer than that in trinucleotide SSRs. Dinucleotide SSRs showed higher polymorphism frequency for genomic SSRs when compared to trinucleotide SSRs, while for EST-SSRs, the frequency of polymorphic SSRs was higher in trinucleotide SSRs than in dinucleotide SSRs. The correlation of the length of SSR and the frequency of polymorphism revealed that the frequency of polymorphism was decreased as motif repeat number increased. Conclusions The assembled polymorphic SSRs would enhance the density of the existing genetic maps of peanut, which could also be a useful source of DNA markers suitable for high-throughput QTL mapping and marker-assisted selection in peanut improvement and thus would be of value to breeders.

  3. Pentanucleotide repeat polymorphism, lipoprotein(a) levels, and risk of ischemic heart disease

    Kamstrup, P.R.; Tybjaerg-Hansen, A.; Steffensen, R.; Nordestgaard, B.G.


    CONTEXT: Lipoprotein(a) is a cardiovascular risk factor. Levels of lipoprotein(a) are predominantly determined by apolipoprotein(a) gene variation, including a pentanucleotide repeat promoter polymorphism. OBJECTIVE: We tested the hypothesis that apolipoprotein(a) pentanucleotide repeat genotype...... predicts elevated lipoprotein(a) levels and risk of myocardial infarction (MI) and ischemic heart disease (IHD) in the general population. DESIGN: We used a cohort study of the Danish general population, The Copenhagen City Heart Study, including 10,276 individuals of which 860 and 1,781 developed MI and....... Mean lipoprotein(a) levels were 40, 36, and 27 mg/dl for individuals with 14-15, 16, and 17-22 repeats (sum of repeats on both alleles), respectively (trend, P < 0.001). Cumulative incidence of MI and IHD was increased for individuals with 14-15 vs. at least 16 repeats (log rank, P < 0.001 and P = 0...

  4. Association between a Tetranucleotide Repeat Polymorphism of SPAG16 Gene and Cataract in Male Children

    Shipra Mehra


    Full Text Available Purpose. Studies involving genotyping of STR markers at 2q34 have repeatedly found the region to host the disease haplotype for pediatric cataract. Present study investigated the association of D2S2944 marker, in sperm associated antigen 16 (SPAG16 gene and rs2289917 polymorphism, in γ-crystallin B gene, with childhood cataract. Methods. 97 pediatric cataract cases and 110 children with no ocular defects were examined for tetranucleotide repeat marker/SNP using PCR-SSLP/RFLP techniques. Polymorphisms were assessed for association using contingency tables and linkage disequilibrium among alleles of the markers was estimated. Energy-optimization program predicted the secondary structure models of repeats of D2S2944. Results. Seven alleles of D2S2944, with 9–15 “GATA” repeats, were observed. Frequency of the longer allele of D2S2944, ≥(GATA13 repeats, was 0.73 in cases and 0.56 in controls (P=0.0123. Male children bearing ≥(GATA13 repeats showed >3-fold higher risk for cataract (CI95% = 1.43–7.00, P=0.0043, Pc=0.0086 as compared to female children (OR=1.19, CI95% = 0.49–2.92, P=0.70. Cases with haplotype—≥(GATA13 of D2S2944 and “C” allele rs2289917—have a higher risk for pediatric cataract (OR=2.952, CI95% = 1.595~5.463, P=0.000453. >(GATA13 repeats formed energetically more favorable stem-loop structure. Conclusion. Intragenic microsatellite repeat expansion in SPAG16 gene increases predisposition to pediatric cataract by probably interfering posttranscriptional events and affecting the expression of adjacent lens transparency gene/s in a gender bias manner.

  5. Biological activity of the virulence factor cagA of Helicobacter pylori

    朱永良; 郑树; 钱可大; 方平楚


    Background China is one of the countries with the highest incidence of H. Pylori and more than 9090 isolates possessed the cagA gene. This study was to evaluate the biological activity of the H.pylori virulence factor cagA isolated from Chinese patients. Methods cagA DNA fragments were amplified from the genomic DNA and subsequently cloned into the mammalian expression vector for cell transfection and DNA sequencing. cagA protein, phosphorylated-tyrosine cagA and the complex of cagA precipitated with SHP-2 were identified respectively by western blot in the crude cell lysate from conditionally immortalized gastric epithelial cells at 48 hours after transfection with cagA DNA. In addition, the ability of induction of scattering phenotype was examined after transient expression of cagA in AGS cells. Results The C-terminal half of cagA contained only one repeated sequence and three tandem five-amino-acid motifs glutamic acid-proline-isoleucine-tyrosine-alanine (EPIYA). Moreover, the amino acid sequence of D2 region in repeated sequence was aspartic acid-phenylanaline-aspartic acid (D-F-D) which was significantly distinguished from the three repeated sequences and aspartic acid-aspartic adid-leucine (D-D-L) in the western standard strain NCTC11637. Western blot revealed that cagA became phosphorylated in tyrosine site and bound with SHP-2 after transient expression of cagA DNA in gastric epithelial cells. Transient expression of cagA in AGS cells showed that cagA was able to induce the elongation phenotype although to a lesser extent than western strains. Conclusions cagA perturbs cell signaling pathways by binding with SHP-2. However, significant difference exists in amino acid sequence and biological function of cagA in Chinese compared with those of western countries.

  6. A polymorphic repeat in the IGF1 promoter influences the risk of endometrial cancer

    Katherine A Bolton


    Full Text Available Due to the lack of high-throughput genetic assays for tandem repeats, there is a paucity of knowledge about the role they may play in disease. A polymorphic CA repeat in the promoter region of the insulin-like growth factor 1 gene (IGF1 has been studied extensively over the past 10 years for association with the risk of developing breast cancer, among other cancers, with variable results. The aim of this study was to determine if this CA repeat is associated with the risk of developing breast cancer and endometrial cancer. Using a case–control design, we analysed the length of this CA repeat in a series of breast cancer and endometrial cancer cases and compared this with a control population. Our results showed an association when both alleles were considered in breast and endometrial cancers (P=0.029 and 0.011, respectively, but this did not pass our corrected threshold for significance due to multiple testing. When the allele lengths were analysed categorically against the most common allele length of 19 CA repeats, an association was observed with the risk of endometrial cancer due to a reduction in the number of long alleles (P=0.013. This was confirmed in an analysis of the long alleles separately for endometrial cancer risk (P=0.0012. Our study found no association between the length of this polymorphic CA repeat and breast cancer risk. The significant association observed between the CA repeat length and the risk of developing endometrial cancer has not been previously reported.

  7. A polymorphic repeat in the IGF1 promoter influences the risk of endometrial cancer

    Bolton, Katherine A; Avery-Kiejda, Kelly A; Holliday, Elizabeth G; Attia, John; Bowden, Nikola A


    Due to the lack of high-throughput genetic assays for tandem repeats, there is a paucity of knowledge about the role they may play in disease. A polymorphic CA repeat in the promoter region of the insulin-like growth factor 1 gene (IGF1 has been studied extensively over the past 10 years for association with the risk of developing breast cancer, among other cancers, with variable results. The aim of this study was to determine if this CA repeat is associated with the risk of developing breast cancer and endometrial cancer. Using a case–control design, we analysed the length of this CA repeat in a series of breast cancer and endometrial cancer cases and compared this with a control population. Our results showed an association when both alleles were considered in breast and endometrial cancers (P=0.029 and 0.011, respectively), but this did not pass our corrected threshold for significance due to multiple testing. When the allele lengths were analysed categorically against the most common allele length of 19 CA repeats, an association was observed with the risk of endometrial cancer due to a reduction in the number of long alleles (P=0.013). This was confirmed in an analysis of the long alleles separately for endometrial cancer risk (P=0.0012). Our study found no association between the length of this polymorphic CA repeat and breast cancer risk. The significant association observed between the CA repeat length and the risk of developing endometrial cancer has not been previously reported. PMID:27090263

  8. A study of allelic polymorphism of four short tandem repeats in the population of northwestern Russia

    Aseev, M.V.; Skakun, V.N.; Baranov, V.S. [Ott Institute of Obstetrics and Gynecology, St. Petersburg (Russian Federation)


    Characteristics of the allelic polymorphisms of the trimeric AGC repeat of the androgen receptor gene (Xq11-12), exon 1 (AR); the tetrameric ATCT repeat of the von Willebrand factor gene (12p12), intron 40 (vWF); the AGAT repeat of the hypoxanthine phosphoribosyltransferase gene (Xq26) (HPRT); and the AGAT repeat of anonymous DNA sequences of the short arm of chromosome X (STRX1) were studied in 160 DNA samples from unrelated inhabitants of northwestern Russia using the method of polymerase chain reaction. Seventeen, ten, eight, and nine alleles were revealed electrophoretically for short tandem repeats of AR, vWF, HPRT, and STRX1, respectively. The heterozygosity indices for these repeats were 0.80, 0.70, 0.54, and 0.58, respectively. The values for AR and vWF correlated with those expected according to the Hardy-Weinberg equilibrium, whereas the values for HPRT and STRX1 differed significantly from those theoretically expected. The individualization potentials were 0.045, 0.135, 0.095, and 0.061 for the short tandem repeats of AR, vWF, HPRT, and STRX1, respectively. The distribution of genotypes for the set of these four loci in the population studied was determined. The possibilities of using the studied polymorphic marker systems in molecular diagnosis of the corresponding monogenic diseases - spinal and bulbar muscle atrophy (AR), Lesch-Nyhan disease (HPRT), and von Willebrand disease (vWF) - as well as in population human genetics, testing of personal identity, and molecular approaches to the estimation of mutagenic activity are discussed. 17 refs., 2 figs., 6 tabs.

  9. Development and characterization of highly polymorphic long TC repeat microsatellite markers for genetic analysis of peanut

    Macedo Selma E


    Full Text Available Abstract Background Peanut (Arachis hypogaea L. is a crop of economic and social importance, mainly in tropical areas, and developing countries. Its molecular breeding has been hindered by a shortage of polymorphic genetic markers due to a very narrow genetic base. Microsatellites (SSRs are markers of choice in peanut because they are co-dominant, highly transferrable between species and easily applicable in the allotetraploid genome. In spite of substantial effort over the last few years by a number of research groups, the number of SSRs that are polymorphic for A. hypogaea is still limiting for routine application, creating the demand for the discovery of more markers polymorphic within cultivated germplasm. Findings A plasmid genomic library enriched for TC/AG repeats was constructed and 1401 clones sequenced. From the sequences obtained 146 primer pairs flanking mostly TC microsatellites were developed. The average number of repeat motifs amplified was 23. These 146 markers were characterized on 22 genotypes of cultivated peanut. In total 78 of the markers were polymorphic within cultivated germplasm. Most of those 78 markers were highly informative with an average of 5.4 alleles per locus being amplified. Average gene diversity index (GD was 0.6, and 66 markers showed a GD of more than 0.5. Genetic relationship analysis was performed and corroborated the current taxonomical classification of A. hypogaea subspecies and varieties. Conclusions The microsatellite markers described here are a useful resource for genetics and genomics in Arachis. In particular, the 66 markers that are highly polymorphic in cultivated peanut are a significant step towards routine genetic mapping and marker-assisted selection for the crop.

  10. Androgen receptor gene polymorphisms are associated with aggression in Japanese Akita Inu

    Konno, Akitsugu; Inoue-Murayama, Miho; Hasegawa, Toshikazu


    We tested for an association between variable number of tandem repeats in the canine androgen receptor (AR) gene and personality differences in Japanese Akita Inu dogs. The polymorphic trinucleotide (CAG) repeat region coding for glutamine in exon 1 of the AR gene was genotyped using genomic DNA obtained from 171 dogs. Three alleles (23, 24 and 26 repeats) were detected, and the allele frequency differed with the coat colour. We assessed the personality profiles of 100 fawn-coloured dogs (54 ...

  11. Analysis of Y-chromosomal short tandem repeat (STR) polymorphism in an Iranian Sadat population.

    Rafiee, M R; Sokhansanj, A; Naghizadeh, M A; Farazmand, A


    The molecular genotyping of individuals and reconstruction of kinship through short and highly polymorphic DNA markers, so called short tandem repeats (STR), has become one of the important and efficient methods in anthropology studies and forensic science. Although many populations have been analyzed, no study has yet been carried out on Sadat populations who are putative descendents of Prophet Mohammad (peace be upon him). Polymorphisms of 6 Y-STR loci (DYS19, DYS385a/b, DYS389II, DYS390, DYS392, and DYS393) have been studied in an unrelated population of Sadat males. The aim of this study was to find possible similarities within Sadat males, resided in Iran. Among Sadat, DYS385b was proved to be the most polymorphic (GD = 0.8588), and DYS392 showed the lowest polymorphism (GD = 0.3527). In 50 samples, 45 different haplotypes were found, of which 39 haplotypes were unique. In the study, three samples had multi-allelic patterns. Haplotype diversity, in regard to these 7 markers was 0.9942. PMID:19769300

  12. Conservation of human chromosome 13 polymorphic microsatellite (CA){sub n} repeats in chimpanzees

    Deka, R.; Shriver, M.D.; Yu, L.M. [Univ. of Pittsburgh, PA (United States)] [and others


    Tandemly repeated (dC-dA){sub n} {center_dot} (dG-dT){sub n} sequences occur abundantly and are found in most eukaryotic genomes. To investigate the level of conservation of these repeat sequences in nonhuman primates, the authors have analyzed seven human chromosome 13 dinucleotide (CA){sub n} repeat loci in chimpanzees by DNA amplification using primers designed for analysis of human loci. Comparable levels of polymorphism at these loci in the two species, revealed by the number of alleles, heterozygosity, and allele sizes, suggest that the (CA){sub n} repeat arrays and their genomic locations are highly conserved. Even though the proportion of shared alleles between the two species varies enormously and the modal alleles are not the same, allelic lengths at each locus in the chimpanzees are detected within the bounds of the allele size range observed in humans. A similar observation has been noted in a limited number of gorillas and orangutans. Using a new measure of genetic distance that takes into account the size of alleles, they have compared the genetic distance between humans and chimpanzees. The genetic distance between these two species was found to be ninefold smaller than expected assuming there is no selection or mutational bias toward retention of (CA){sub n} repeat arrays. These findings suggest a functional significance for these microsatellite loci. 34 refs., 1 fig., 2 tabs.

  13. γA gene repeats polymorphism for the analysis of haplotypes of abnormal hemoglobins

    Nejat Akar


    Full Text Available Aim of this study was to analyze γ A gene repeat polymorphism for the analysis of haplotypes of hemoglobin (Hb variants such as Hb S, Hb D-Punjab, Hb O-Arab. Sickle cell cases had mainly Benin and Arab/Indian haplotype. We found three different haplotypes among Hb S, Hb O Arab and Hb D-Punjab cases. We named these three variants as Anatolian-1 and Anatolian-2 and Asian. Our data revealed that Hb O Arab may arise twice one from Asia and the other from Europe.

  14. Simple sequence repeats in Neurospora crassa: distribution, polymorphism and evolutionary inference

    Park Jongsun


    Full Text Available Abstract Background Simple sequence repeats (SSRs have been successfully used for various genetic and evolutionary studies in eukaryotic systems. The eukaryotic model organism Neurospora crassa is an excellent system to study evolution and biological function of SSRs. Results We identified and characterized 2749 SSRs of 963 SSR types in the genome of N. crassa. The distribution of tri-nucleotide (nt SSRs, the most common SSRs in N. crassa, was significantly biased in exons. We further characterized the distribution of 19 abundant SSR types (AST, which account for 71% of total SSRs in the N. crassa genome, using a Poisson log-linear model. We also characterized the size variation of SSRs among natural accessions using Polymorphic Index Content (PIC and ANOVA analyses and found that there are genome-wide, chromosome-dependent and local-specific variations. Using polymorphic SSRs, we have built linkage maps from three line-cross populations. Conclusion Taking our computational, statistical and experimental data together, we conclude that 1 the distributions of the SSRs in the sequenced N. crassa genome differ systematically between chromosomes as well as between SSR types, 2 the size variation of tri-nt SSRs in exons might be an important mechanism in generating functional variation of proteins in N. crassa, 3 there are different levels of evolutionary forces in variation of amino acid repeats, and 4 SSRs are stable molecular markers for genetic studies in N. crassa.

  15. Efficacy Improvement of PCR Amplification of CAG Trinucleotide Repeats in the Coding Sequence of Spinocerebellar Ataxia Type II Gene%提高SCA2编码区CAG三核苷酸重复的PCR扩增效率

    汤熙翔; 夏家辉


    To improve the efficacy of PCR amplification of CAG trinucleotide repeats in the coding sequence of spinocerebellar ataxia type II gene(69.2% G+C), hot-start PCR, base-replacement PCR, and the addition of enhancers(1%~12.5% DMSO , 1%~25% glycerol ,1%~12.5% formamide) were performed and compared with normal PCR . The results showed that hot-start PCR, base-replacement PCR and the addition of enhancers(1%~10% DMSO , 5%~20% glycerol , 1%~10% formamide) improved the amplification efficacy of the GC rich region. Gene diagnosis in 70 SCA pedgrees and 60 spontaneous SCA patients were also conducted.%以遗传性脊髓小脑共济失调II型基因(spinocerebellar ataxia type II gene SCA2)编码区内的CAG三核苷酸重复为研究对象(G+C含量为69.2%),比较了热启动PCR、碱基替代PCR、添加增效剂(1%~12.5%二甲亚砜、1%~25%甘油、1%~12.5%甲酰胺)与常规PCR的扩增效率,发现热启动PCR、碱基替代PCR及添加增效剂(1%~10%二甲亚砜、5%~20%甘油、1%~10%甲酰胺)能提高该GC富集区的扩增效率,并对70个SCA家系及60个散发SCA患者进行了SCA2的基因诊断。

  16. Polymorphism in the HASPB repeat region of East African Leishmania donovani strains.

    Arie Zackay

    Full Text Available BACKGROUND/OBJECTIVES: Visceral leishmaniasis (VL caused by Leishmania donovani is a major health problem in Ethiopia. Parasites in disparate regions are transmitted by different vectors, and cluster in distinctive genotypes. Recently isolated strains from VL and HIV-VL co-infected patients in north and south Ethiopia were characterized as part of a longitudinal study on VL transmission. METHODOLOGY/PRINCIPAL FINDINGS: Sixty-three L. donovani strains were examined by polymerase chain reaction (PCR targeting three regions: internal transcribed spacer 1 (ITS1, cysteine protease B (cpb, and HASPB (k26. ITS1- and cpb--PCR identified these strains as L. donovani. Interestingly, the k26--PCR amplicon size varied depending on the patient's geographic origin. Most strains from northwestern Ethiopia (36/40 produced a 290 bp product with a minority (4/40 giving a 410 bp amplicon. All of the latter strains were isolated from patients with HIV-VL co-infections, while the former group contained both VL and HIV-VL co-infected patients. Almost all the strains (20/23 from southwestern Ethiopia produced a 450 bp amplicon with smaller products (290 or 360 bp only observed for three strains. Sudanese strains produced amplicons identical (290 bp to those found in northwestern Ethiopia; while Kenyan strains gave larger PCR products (500 and 650 bp. High-resolution melt (HRM analysis distinguished the different PCR products. Sequence analysis showed that the k26 repeat region in L. donovani is comprised of polymorphic 13 and 14 amino acid motifs. The 13 amino acid peptide motifs, prevalent in L. donovani, are rare in L. infantum. The number and order of the repeats in L. donovani varies between geographic regions. CONCLUSIONS/SIGNIFICANCE: HASPB repeat region (k26 shows considerable polymorphism among L. donovani strains from different regions in East Africa. This should be taken into account when designing diagnostic assays and vaccines based on this antigen.

  17. The EPIYA-ABCC motif pattern in CagA of Helicobacter pylori is associated with peptic ulcer and gastric cancer in Mexican population

    Beltrán-Anaya, Fredy Omar; Poblete, Tomás Manuel; Román-Román, Adolfo; Reyes, Salomón; de Sampedro, José; Peralta-Zaragoza, Oscar; Rodríguez, Miguel Ángel; del Moral-Hernández, Oscar; ILLADES-AGUIAR, BERENICE; Fernández-Tilapa, Gloria


    Background Helicobacter pylori chronic infection is associated with chronic gastritis, peptic ulcer, and gastric cancer. Cytotoxin-associated gene A (cagA)-positive H. pylori strains increase the risk of gastric pathology. The carcinogenic potential of CagA is linked to its polymorphic EPIYA motif variants. The goals of this study were to investigate the frequency of cagA-positive Helicobacter pylori in Mexican patients with gastric pathologies and to assess the association of cagA EPIYA moti...

  18. Estrogen receptor alpha dinucleotide repeat polymorphism in Japanese patients with autoimmune thyroid diseases

    Tozaki Teruaki


    Full Text Available Abstract Background The autoimmune thyroid diseases (AITDs, comprising Graves' disease (GD and Hashimoto's thyroiditis (HT, appear to develop as a result of complex interactions between predisposing genes and environmental triggers. Susceptibility to AITDs is conferred by genes in the human leukocyte antigen (HLA and genes unlinked to HLA, including the CTLA-4 gene. Recently, an association to some estrogen receptor (ERα genotypes with breast cancer, hypertension, osteoporosis, generalized osteoarthritis, and some autoimmune diseases such as rheumatoid arthritis has been reported. We have analyzed a dinucleotide (TAn repeat polymorphism lying upstream of the human ERα gene in patients with AITDs and in normal subjects. Results Seventeen different alleles were found in 130 patients with GD, 93 patients with HT, and 190 control subjects. There was no significant difference in the distributions of ERα alleles between patients and controls. Conclusions The present results do not support an association between the ERα gene and AITD in the Japanese population.

  19. Normal ATXN3 allele but not CHIP polymorphisms modulates age at onset in Machado-Joseph Disease

    Marcondes C. França Jr


    Full Text Available Background: Age at onset (AO in Machado-Joseph disease (MJD is closely associated with the length of the CAG repeat at the mutant ATXN3 allele, but there are other intervening factors. Experimental evidence indicates that the normal ATXN3 allele and the C-terminal heat shock protein 70 (Hsp70-interacting protein (CHIP may be genetic modifiers of AO in MJD. Methods: To investigate this hypothesis, we determined the length of normal and expanded CAG repeats at the ATXN3 gene in 210 unrelated patients with MJD. In addition, we genotyped five single nucleotide polymorphisms (SNPs within the CHIP gene. We first compared the frequencies of the different genotypes in two subgroups of patients who were highly discordant for AO after correction for the length of the expanded CAG allele. The possible modifier effect of each gene was then evaluated in a stepwise multiple linear regression model. Results: AO was associated with the length of the expanded CAG allele (r2 = 0.596, p<0.001. Frequencies of the normal CAG repeats at the ATXN3 gene and of CHIP polymorphisms did not differ significantly between groups with highly discordant ages at onset. However, addition of the normal allele improved the model fit for prediction of AO (r2 = 0.604, p=0.014. Indeed, we found that the normal CAG allele at ATXN3 had a positive independent effect on AO. Conclusion: The normal CAG repeat at the ATXN3 gene has a small but significant influence on AO of MJD.

  20. Robertsonian fusions, pericentromeric repeat organization and evolution : a case study within a highly polymorphic rodent species, Gerbillus nigeriae

    Gauthier, Philippe; Hima, Karmadine; Dobigny, Gauthier


    Pericentromeric repeats have been claimed to mediate centric fusions through heterologous recombination of arrays of tandemly repeated and highly homogenized motifs. However, mammalian case studies are essentially restricted to pathologic fusions in human, or to the house mouse Roberstonian (Rb) races. We here provide an example in a wild gerbil rodent, Gerbillus nigeriae, which displays an extensive Rb polymorphism, with 2n ranging between 2n = 60 and 74. The distribution of two closely rela...

  1. Helicobacter pylori CagL Hypervariable Motif: A Global Analysis of Geographical Diversity and Association With Gastric Cancer.

    Gorrell, Rebecca J; Zwickel, Nicolas; Reynolds, John; Bulach, Dieter; Kwok, Terry


    Previous studies suggest overrepresentation of particular polymorphisms within the Helicobacter pylori CagL hypervariable motif (CagLHM) in gastric cancer-associated isolates. However, these disease correlations were geographically variable and ambiguous. We compared the disease correlation of several hundred geographically diverse CagL sequences and identified 33 CagLHM sequence combinations with disparate geographical distribution, revealing substantial worldwide CagLHM diversity, particularly within Asian countries. Notably, polymorphisms E59 and I60 were significantly overrepresented, whereas D58 and E62 were underrepresented, in gastric cancer-associated H. pylori isolates worldwide. Thus, CagLHM regional diversity may contribute to the varied prevalence of H. pylori-related gastric cancer observed in diverse populations. PMID:26908724

  2. Phylogenetic relationship of the populations within and around Japan using 105 short tandem repeat polymorphic loci.

    Li, Shi-Lin; Yamamoto, Toshimichi; Yoshimoto, Takashi; Uchihi, Rieko; Mizutani, Masaki; Kurimoto, Yukihide; Tokunaga, Katsushi; Jin, Feng; Katsumata, Yoshinao; Saitou, Naruya


    We have analyzed 105 autosomal polymorphic short tandem repeat (STR) loci for nine East and South-eastern Asian populations (two Japanese, five Han Chinese, Thai, and Burmese populations) and a Caucasian population using a multiplex PCR typing system. All the STR loci are genomewide tetranucleotide repeat markers of which the total number of observed alleles and the observed heterozygosity were 756 and 0.743, respectively, for Japanese populations. Phylogenetic analysis for these allele frequency data suggested that the Japanese populations are more closely related with southern Chinese populations than central and/or northern ones. STRUCTURE program analysis revealed the almost clearly divided and accountable population structure at K=2-6, that the two Japanese populations always formed one group separated from the other populations and never belong to different groups at K> or =3. Furthermore, our new allele frequency data for 91 loci were analyzed with those for 52 worldwide populations published by previous studies. Phylogenetic and multidimensional scaling (MDS) analyses indicated that Asian populations with large population size (six Han Chinese, three Japanese, two Southeast Asia) formed one distinct cluster and are closer to each other than other ethnic minorities in east and Southeast Asia. This pattern may be the caviar of comparing populations with greatly differing population sizes when STR loci were analyzed. PMID:16315063

  3. A high-density simple sequence repeat and single nucleotide polymorphism genetic map of the tetraploid cotton genome

    Cotton genome complexity was investigated with a saturated molecular genetic map that combined several sets of microsatellites or simple sequence repeats (SSR) and the first major public set of single nucleotide polymorphism (SNP) markers in cotton genomes (Gossypium spp.), and that was constructed ...

  4. A comprehensive sequence and disease correlation analyses for the C-terminal region of CagA protein of Helicobacter pylori.

    Youlin Xia

    Full Text Available Chronic Helicobacter pylori infection is known to be associated with the development of peptic ulcer, gastric cancer and gastric lymphoma. Currently, the bacterial factors of H. pylori are reported to be important in the development of gastroduodenal diseases. CagA protein, encoded by the cagA, is the best studied virulence factor of H. pylori. The pathogenic CagA protein contains a highly polymorphic Glu-Pro-Ile-Tyr-Ala (EPIYA repeat region in the C-terminal. This repeat region is reported to be involved in the pathogenesis of gastroduodenal diseases. The segments containing EPIYA motifs have been designated as segments A, B, C, and D; however the classification and disease relation are still unclear. This study used 560 unique CagA sequences containing 1,796 EPIYA motifs collected from public resources, including 274 Western and 286 East Asian strains with clinical data obtained from 433 entries. Fifteen types of EPIYA or EPIYA-like sequences are defined. In addition to four previously reported major segment types, several minor segment types (e.g., segment B', B'' and more than 30 sequence types (e.g., ABC, ABD were defined using our classification method. We confirm that the sequences from Western and East Asian strains contain segment C and D, respectively. We also confirm that strains with two EPIYA segment C have a greater chance of developing gastric cancer than those with one segment C. Our results shed light on the relationships between the types of CagAs, the country of origin of each sequence type, and the frequency of gastric disease.

  5. 直接检测IT15基因(CAG)n重复对亨廷顿氏病进行基因诊断%Direct Detection of the Expanded CAG Repeat in IT15 Gene for Molecular Diagnosis of Huntington's Disease

    毛跃华; 周刚; 陈美珏; 任兆瑞; 曾溢滔; 王秀英; 许志大



  6. Psychiatric symptoms and CAG expansion in Huntington`s disease

    Weber, M.W.; Schmid, W.; Spiegel, R. [Univ. of Zuerich (Switzerland)


    The mutation responsible for Huntington`s disease (HD) is an elongated CAG repeat in the coding region of the IT15 gene. A PCR-based test with high sensitivity and accuracy is now available to identify asymptomatic gene carriers and patients. An inverse correlation between CAG copy number and age at disease onset has been found in a large number of affected individuals. The influence of the CAG repeat expansion on other phenotypic manifestations, especially specific psychiatric symptoms has not been studied intensively. In order to elucidate this situation we investigated the relation between CAG copy number and distinct psychiatric phenotypes found in 79 HD-patients. None of the four differentiated categories (personality change, psychosis, depression, and nonspecific alterations) showed significant differences in respect to size of the CAG expansion. In addition, no influence of individual sex on psychiatric presentation could be found. On the other hand in patients with personality changes maternal transmission was significantly more frequent compared with all other groups. Therefore we suggest that clinical severity of psychiatric features in HD is not directly dependent on the size of the dynamic mutation involved. The complex pathogenetic mechanisms leading to psychiatric alterations are still unknown and thus genotyping does not provide information about expected psychiatric symptoms in HD gene carriers. 40 refs., 1 fig., 2 tabs.

  7. Intraspecific differentiation of Hancornia speciosa revealed by simple sequence repeat and random amplified polymorphic DNA markers.

    Nogueira, C A; Stafuzza, N B; Ribeiro, T P; Prado, A D L; Menezes, I P P; Peixoto, N; Gonçalves, P J; Almeida, L M


    Hancornia speciosa, popularly known as mangabeira, is a fruit tree native to the Brazilian Cerrado that shows great economic potential, due to its multiple uses. Intraspecific classification of this species is difficult because it shows high morphological diversity. An early study of the species reported that there are six botanic varieties that differ morphologically mainly in the shapes of their leaves and flowers. Except to note the wide morphological variation and economic potential of this species, few studies have been published about the genetic diversity of mangabeira. Knowledge of the genetic variability of this species among populations would be useful for genetic conservation and breeding programs. Therefore, we tested the transferability of 12 simple sequence repeats from expressed sequence tags (EST-SSRs) from Catharanthus roseus to H. speciosa and used 10 random amplified polymorphic DNA markers to evaluate the genetic variability among botanical varieties of H. speciosa. We obtained a high transferability frequency of EST-SSR markers from C. roseus to H. speciosa (75%). However, EST-SSR markers showed low heterozygosity and locus variability (two or three alleles by locus), which suggest low genetic diversity in the mangabeira samples. The Jaccard dissimilarity index and an examination of geographic distances indicated a non-spatial structuring of the genetic variability. Our markers were unable to distinguish H. speciosa botanical varieties. PMID:26662392

  8. Robertsonian fusions, pericentromeric repeat organization and evolution: a case study within a highly polymorphic rodent species, Gerbillus nigeriae.

    Gauthier, Philippe; Hima, Karmadine; Dobigny, Gauthier


    Pericentromeric repeats have been claimed to mediate centric fusions through heterologous recombination of arrays of tandemly repeated and highly homogenized motifs. However, mammalian case studies are essentially restricted to pathologic fusions in human, or to the house mouse Roberstonian (Rb) races. We here provide an example in a wild gerbil rodent, Gerbillus nigeriae, which displays an extensive Rb polymorphism, with 2n ranging between 2n = 60 and 74. The distribution of two closely related repeats, GERB1 and GERB2 that were previously isolated by Volobouev et al. (Chromosoma 104:252-259, 1995) in this African species, were investigated in the genomes of seven individuals with various diploid numbers. Our results clearly show that GERB1 and GERB2 are organized in a non-random manner, with GERB2 and GERB1 being clearly juxtacentromeric and centromeric, respectively. Finally, cloning and sequencing revealed that, unlike GERB2, GERB1 monomers display a more homogeneous organization at both the nucleotide and structural levels. Altogether, our results point toward a pivotal role of GERB1 repeats in the mediation of Rb fusions through heterologous recombination, with some evidence of subsequent loss of repeats after the Rb fusion during the course of evolution of metacentric elements. Moreover, the repeat pattern observed in G. nigeriae closely matches the organization and sequence structure of satellite DNAs described in human acrocentrics. Consequently, G. nigeriae appears as an additional model for the study of repeat evolution and its role in centric fusions and their consequences in mammals. PMID:20361248

  9. Characterization of CagA variable region of Helicobacter pylori isolates from Chinese patients

    Yong-Liang Zhu; Shu Zheng; Qin Du; Ke-Da Qian; Ping-Chu Fang


    AIM: To characterize the CagA variable region of Helicobacter pylori isolates from Chinese patients.METHODS: DNA fragments in CagA variable region were amplified and sequenced respectively from genomic DNA of 19 isolates from patients with gastric cancer and 20isolates from patients with chronic gastritis. The tendency of phosphorylation in tyrosine(s) of CagA proteins was evaluated subsequently by phosphorylation assay in vivo and in vitro respectively.RESULTS: About 97.44% (38/39) H pylori isolates possessed CagA gene. CagA+ strains contained 2-4tandem five-amino-acid motifs EPIYA but only one EPIYA had repeated sequence in CagA variable region in different isolates. There was no significant difference between the number of EPIYA motifs in H pylori from patients with different diseases. However, only tyrosine site in EPIYA within repeated sequence could be phosphorylated by AGS cells in vivo although all tyrosine sites in EPIYA could be phosphorylated in vitro.CONCLUSION: CagA in Chinese has no functional difference in perturbing cellular signal pathway among different H pylori isolates.

  10. Adaptive gains through repeated gene loss: parallel evolution of cyanogenesis polymorphisms in the genus Trifolium (Fabaceae)

    Olsen, Kenneth M.; Kooyers, Nicholas J.; Small, Linda L.


    Variation in cyanogenesis (hydrogen cyanide release following tissue damage) was first noted in populations of white clover more than a century ago, and subsequent decades of research have established this system as a classic example of an adaptive chemical defence polymorphism. Here, we document polymorphisms for cyanogenic components in several relatives of white clover, and we determine the molecular basis of this trans-specific adaptive variation. One hundred and thirty-nine plants, repre...

  11. Short tandem repeat polymorphism linkage studies in a new family with X-linked mental retardation (MRX20)

    Lazzarini, A.; Stenroos, E.S.; McKoy, V. [Robert Wood Johnson Medical School, New Brunswick, NJ (United States)] [and others


    A family with X-linked recessive mental retardation (XLMR) without other obvious manifestations (MRX20) was studied with 14 short tandem repeat polymorphism (STRP) markers. Two-point lod scores above 3 were obtained with DXS1003, DXYS1, DXS3, and DXS458. A multipoint lod score of 4.25 was obtained with peak at DXS1003. Recombination events identify a 55.6 cM interval between DXS1068 and DXS454, while a one unit support interval identifies 40 cM between MAOA and DXS458. 42 refs., 2 figs., 3 tabs.

  12. Glycoprotein I of herpes simplex virus type 1 contains a unique polymorphic tandem-repeated mucin region

    Norberg, Peter; Olofsson, Sigvard; Tarp, Mads Agervig;


    Glycoprotein I (gI) of herpes simplex virus type 1 (HSV-1) contains a tandem repeat (TR) region including the amino acids serine and threonine, residues that can be utilized for O-glycosylation. The length of this TR region was determined for 82 clinical HSV-1 isolates and the results revealed......-glycosylation not only for the two most commonly expressed N-acetyl-d-galactosamine (GalNAc)-T1 and -T2 transferases, but also for the GalNAc-T3, -T4 and -T11 transferases. Immunoblotting of virus-infected cells showed that gI was exclusively O-glycosylated with GalNAc monosaccharides (Tn antigen). A polymorphic mucin...... region has not been described previously for HSV-1 and is a unique finding, as repeated blocks within gI homologues are lacking in other alphaherpesviruses....

  13. Prenatal diagnosis of familial dysautonomia by analysis of linked CA-repeat polymorphisms on chromosome 9q31-q33

    Eng, C.M.; Desnick, R.J. [Mount Sinai School of Medicine, New York, NY (United States); Slaugenhaupt, S.A.; Gusella, J.F. [Harvard Medical School, Boston, MA (United States)] [and others


    Familial dysautonomia (FD) is an autosomal recessive sensory neuropathy that affects about 1 in 3,700 individuals of Ashkenazi Jewish ancestry. The underlying biochemical and genetic defects are unknown, thereby precluding prenatal diagnosis in at-risk families. Recently, the FD gene (DYS) was mapped with strong linkage disequilibrium to polymorphic markers in the chromosome 9 region q31-q33. In this report, the use of these markers for the prenatal diagnosis of FD by linkage analysis in families with a previously affected child was evaluated. Genomic DNA from appropriate family members was analyzed to construct haplotypes using informative CA repeat polymorphisms closely linked to and flanking the FD locus. The calculation of risk for the prenatal diagnoses was performed by linkage analysis. All seven FD families were informative for the closely linked polymorphic markers and fetal diagnoses were made in eight pregnancies. Six fetal diagnoses were predicted with >98% accuracy, while two with recombinations were predicted with at least 88% and 92% accuracy. Use of these closely linked markers permitted the reliable prenatal diagnosis of FD in families with a previously affected child. 14 refs., 3 figs.

  14. [Tissue-specific Changes in the Polymorphism of Simple Repeats in DNA of the Offspring of Different Sex Born from Irradiated Male or Female Mice].

    Lomaeva, M G; Fomenko, L A; Vasil'eva, G V; Bezlepkin, V G


    Evidence is presented indicating the differences in the polymorphism of microsatellite (MCS) repeats in DNA of somatic tissues in the offspring of BALB/c mice of different sex born from preconceptionally irradiated males or females. Brother-sister groups of the offspring born by non-irradiated parental pairs were compared with the offspring obtained after the irradiation of one parent in the same pairs. The number of MCS repeats in DNA of somatic tissues of the offspring from irradiated males or females was compared by a polymerase chain reaction using an arbitrary primer. It was found that changes in the polymorphism of the number of MCS repeats in the offspring from the males irradiated at a dose of 2 Gy was insignificant as compared with the offspring from control animals. In the offspring born by the females irradiated at a dose of 2 Gy (which does not impair the reproductive capacity), a statistically significant increase in the polymorphism was observed. Changes in the polymorphism were different in the offspring of different sex. A higher level of polymorphism was revealed in the female offspring born from the females of the F0 generation after their irradiation at a dose of 2 Gy. The increase in the polymorphism of the number of MCS repeats in DNA was more pronounced in postmitotic tissues compared with proliferating tissues. PMID:27534065

  15. Analysis of the AHR gene proximal promoter GGGGC-repeat polymorphism in lung, breast, and colon cancer

    The aryl hydrocarbon receptor (AhR) regulates expression of numerous genes, including those of the CYP1 gene family. With the goal of determining factors that control AHR gene expression, our studies are focused on the role of the short tandem repeat polymorphism, (GGGGC)n, located in the proximal promoter of the human AHR gene. When luciferase constructs containing varying GGGGC repeats were transfected into cancer cell lines derived from the lung, colon, and breast, the number of GGGGC repeats affected AHR promoter activity. The number of GGGGC repeats was determined in DNA from 327 humans and from 38 samples representing 5 species of non-human primates. In chimpanzees and 3 species of macaques, only (GGGGC)2 alleles were observed; however, in western gorilla, (GGGGC)n alleles with n = 2, 4, 5, 6, 7, and 8 were identified. In all human populations examined, the frequency of (GGGGC)n was n = 4 > 5 ≫ 2, 6. When frequencies of the (GGGGC)n alleles in DNA from patients with lung, colon, or breast cancer were evaluated, the occurrence of (GGGGC)2 was found to be 8-fold more frequent among lung cancer patients in comparison with its incidence in the general population, as represented by New York State neonates. Analysis of matched tumor and non-tumor DNA samples from the same individuals provided no evidence of microsatellite instability. These studies indicate that the (GGGGC)n short tandem repeats are inherited, and that the (GGGGC)2 allele in the AHR proximal promoter region should be further investigated with regard to its potential association with lung cancer susceptibility. - Highlights: • The AHR proximal promoter contains a polymorphism, (GGGGC)n, where n = 4 > 5 ≫ 2, 6 • Matched tumor and non-tumor DNA did not show (GGGGC)n microsatellite instability • AHR promoter activity of a construct with (GGGGC)2 was lower than that of (GGGGC)4 • The frequency of (GGGGC)2 in lung cancer patients was 8-fold higher than in neonates • The (GGGGC)2 allele may

  16. Analysis of the AHR gene proximal promoter GGGGC-repeat polymorphism in lung, breast, and colon cancer

    Spink, Barbara C. [Wadsworth Center, New York State Department of Health, Albany, NY 12201 (United States); Bloom, Michael S. [Department of Environmental Health Sciences, School of Public Health, University at Albany, State University of New York, Albany, NY 12201 (United States); Wu, Susan [Wadsworth Center, New York State Department of Health, Albany, NY 12201 (United States); Sell, Stewart; Schneider, Erasmus [Wadsworth Center, New York State Department of Health, Albany, NY 12201 (United States); Department of Biomedical Sciences, School of Public Health, University at Albany, State University of New York, Albany, NY 12201 (United States); Ding, Xinxin [Wadsworth Center, New York State Department of Health, Albany, NY 12201 (United States); Department of Environmental Health Sciences, School of Public Health, University at Albany, State University of New York, Albany, NY 12201 (United States); Department of Biomedical Sciences, School of Public Health, University at Albany, State University of New York, Albany, NY 12201 (United States); Spink, David C., E-mail: [Wadsworth Center, New York State Department of Health, Albany, NY 12201 (United States); Department of Environmental Health Sciences, School of Public Health, University at Albany, State University of New York, Albany, NY 12201 (United States)


    The aryl hydrocarbon receptor (AhR) regulates expression of numerous genes, including those of the CYP1 gene family. With the goal of determining factors that control AHR gene expression, our studies are focused on the role of the short tandem repeat polymorphism, (GGGGC){sub n}, located in the proximal promoter of the human AHR gene. When luciferase constructs containing varying GGGGC repeats were transfected into cancer cell lines derived from the lung, colon, and breast, the number of GGGGC repeats affected AHR promoter activity. The number of GGGGC repeats was determined in DNA from 327 humans and from 38 samples representing 5 species of non-human primates. In chimpanzees and 3 species of macaques, only (GGGGC){sub 2} alleles were observed; however, in western gorilla, (GGGGC){sub n} alleles with n = 2, 4, 5, 6, 7, and 8 were identified. In all human populations examined, the frequency of (GGGGC){sub n} was n = 4 > 5 ≫ 2, 6. When frequencies of the (GGGGC){sub n} alleles in DNA from patients with lung, colon, or breast cancer were evaluated, the occurrence of (GGGGC){sub 2} was found to be 8-fold more frequent among lung cancer patients in comparison with its incidence in the general population, as represented by New York State neonates. Analysis of matched tumor and non-tumor DNA samples from the same individuals provided no evidence of microsatellite instability. These studies indicate that the (GGGGC){sub n} short tandem repeats are inherited, and that the (GGGGC){sub 2} allele in the AHR proximal promoter region should be further investigated with regard to its potential association with lung cancer susceptibility. - Highlights: • The AHR proximal promoter contains a polymorphism, (GGGGC){sub n}, where n = 4 > 5 ≫ 2, 6 • Matched tumor and non-tumor DNA did not show (GGGGC){sub n} microsatellite instability • AHR promoter activity of a construct with (GGGGC){sub 2} was lower than that of (GGGGC){sub 4} • The frequency of (GGGGC){sub 2} in lung

  17. Evolution of cagA oncogene of Helicobacter pylori through recombination.

    Yoshikazu Furuta

    Full Text Available Helicobacter pylori is a gastric pathogen that infects half the human population and causes gastritis, ulcers, and cancer. The cagA gene product is a major virulence factor associated with gastric cancer. It is injected into epithelial cells, undergoes phosphorylation by host cell kinases, and perturbs host signaling pathways. CagA is known for its geographical, structural, and functional diversity in the C-terminal half, where an EPIYA host-interacting motif is repeated. The Western version of CagA carries the EPIYA segment types A, B, and C, while the East Asian CagA carries types A, B, and D and shows higher virulence. Many structural variants such as duplications and deletions are reported. In this study, we gained insight into the relationships of CagA variants through various modes of recombination, by analyzing all known cagA variants at the DNA sequence level with the single nucleotide resolution. Processes that occurred were: (i homologous recombination between DNA sequences for CagA multimerization (CM sequence; (ii recombination between DNA sequences for the EPIYA motif; and (iii recombination between short similar DNA sequences. The left half of the EPIYA-D segment characteristic of East Asian CagA was derived from Western type EPIYA, with Amerind type EPIYA as the intermediate, through rearrangements of specific sequences within the gene. Adaptive amino acid changes were detected in the variable region as well as in the conserved region at sites to which no specific function has yet been assigned. Each showed a unique evolutionary distribution. These results clarify recombination-mediated routes of cagA evolution and provide a solid basis for a deeper understanding of its function in pathogenesis.

  18. Tissue identity testing of cancer by short tandem repeat polymorphism: pitfalls of interpretation in the presence of microsatellite instability.

    Much, Melissa; Buza, Natalia; Hui, Pei


    Tissue identity testing by short tandem repeat (STR) polymorphism offers discriminating power in resolving tissue mix-up or contamination. However, one caveat is the presence of microsatellite unstable tumors, in which genetic alterations may drastically change the STR wild-type polymorphism leading to unexpected allelic discordance. We examined how tissue identity testing results can be altered by the presence of microsatellite instability (MSI). Eleven cases of MSI-unstable (9 intestinal and 2 endometrial adenocarcinomas) and 10 cases of MSI-stable tumors (all colorectal adenocarcinomas) were included. All had been previously tested by polymerase chain reaction testing at 5 National Cancer Institute (NCI) recommended MSI loci and/or immunohistochemistry for DNA mismatch repair proteins (MLH1, MSH2, MSH6, and PMS2). Tissue identity testing targeting 15 STR loci was performed using AmpF/STR Identifiler Amplification. Ten of 11 MSI-unstable tumors demonstrated novel alleles at 5 to 12 STR loci per case and frequently with 3 or more allelic peaks. However, all affected loci showed identifiable germline allele(s) in MSI-high tumors. A wild-type allelic profile was seen in 7 of 10 MSI-stable tumors. In the remaining 3 cases, isolated novel alleles were present at a unique single locus in addition to germline alleles. Loss of heterozygosity was observed frequently in both MSI-stable (6/11 cases) and MSI-unstable tumors (8/10 cases). In conclusion, MSI may significantly alter the wild-type allelic polymorphism, leading to potential interpretation errors of STR genotyping. Careful examination of the STR allelic pattern, high index of suspicion, and follow-up MSI testing are crucial to avoid erroneous conclusions and subsequent clinical and legal consequences. PMID:24444463

  19. Chemical correction of pre-mRNA splicing defects associated with sequestration of muscleblind-like 1 protein by expanded r(CAG) transcripts

    Kumar, Amit; Parkesh, Raman; Sznajder, Lukasz J.; Childs-Disney, Jessica; Sobczak, Krzysztof; Disney, Matthew D.


    Recently, it was reported that expanded r(CAG) triplet repeats (r(CAG)exp) associated with untreatable neurological diseases cause pre-mRNA mis-splicing likely due to sequestration of muscleblind-like 1 (MBNL1) splicing factor. Bioactive small molecules that bind the 5’CAG/3’GAC motif found in r(CAG)exp hairpin structure were identified by using RNA binding studies and virtual screening/chemical similarity searching. Specifically, a benzylguanidine-containing small molecule was found to impro...

  20. CAG tract of MJD-1 may be prone to frameshifts causing polyalanine accumulation.

    Gaspar, C; Jannatipour, M; Dion, P; Laganière, J; Sequeiros, J; Brais, B; Rouleau, G A


    Machado-Joseph disease (MJD) is one of several disorders caused by the expansion of a coding CAG repeat (exp-CAG). The presence of intranuclear inclusions (INIs) in patients and cellular models of exp-CAG-associated diseases has lead to a nuclear toxicity model. Similar INIs are found in oculopharyngeal muscular dystrophy, which is caused by a short expansion of an alanine-encoding GCG repeat. Here we propose that transcriptional or translational frameshifts occurring within expanded CAG tracts result in the production and accumulation of polyalanine-containing mutant proteins. We hypothesize that these alanine polymers deposit in cells forming INIs and may contribute to nuclear toxicity. We show evidence that supports our hypothesis in lymphoblast cells from MJD patients, as well as in pontine neurons of MJD brain and in in vitro cell culture models of the disease. We also provide evidence that alanine polymers alone are harmful to cells and predict that a similar pathogenic mechanism may occur in the other CAG repeat disorders. PMID:10942424

  1. Whole genome evaluation of tandem repeat polymorphisms between two pathogenically similar strains of Xylella fastidiosa isolated from almond and grape in California

    Whole genome tandem repeat polymorphisms were evaluated between two closely related Xylella fastidiosa strains, M23 and Temecula1, both cause almond leaf scorch disease (ALSD) and grape Pierce’s disease (PD) in California. Strain M23 was isolated from almond and the genome was sequenced in this stu...

  2. Improving global and regional resolution of male lineage differentiation by simple single-copy Y-chromosomal short tandem repeat polymorphisms

    M. Vermeulen (Mark); A. Wollstein (Andreas); K. van der Gaag (Kristiaan); O. Lao Grueso (Oscar); Y. Xue (Yali); Q. Wang (Qiuju); L. Roewer (Lutz); H. Knoblauch (Hans); C. Tyler-Smith (Chris); P. de Knijff (Peter); M.H. Kayser (Manfred)


    textabstractWe analyzed 67 short tandem repeat polymorphisms from the non-recombining part of the Y-chromosome (Y-STRs), including 49 rarely studied simple single-copy (ss)Y-STRs and 18 widely used Y-STRs, in 590 males from 51 populations belonging to 8 worldwide regions (HGDP-CEPH panel). Although

  3. Development of Single Nucleotide Polymorphism markers in Theobroma cacao and comparison to Simple Sequence Repeat markers for genotyping of Cameroon clones.

    Single Nucleotide Polymorphism (SNP) markers are increasingly being used in crop breeding programs, slowly replacing Simple Sequence Repeats (SSR) and other markers. SNPs provide many benefits over SSRs, including ease of analysis and unambiguous results across various platforms. We have identifie...

  4. Anthropometry in Klinefelter syndrome - multifactorial influences due to CAG length, testosterone treatment and possibly intrauterine hypogonadism

    Chang, Simon; Skakkebæk, Anne; Trolle, Christian;


    .47)(p<0.02 for all), as well as total fat mass (0.74), abdominal fat mass (0.67) and total body fat percentage (0.84) was increased in KS males (p<0.001 for all), while bitesticular volume was reduced (4.6). AR CAG repeat length was comparable in KS and controls, and among KS CAG correlated to arm...... body composition in KS and relate findings to biochemistry and X-chromosome related genetic markers. Design, setting and participants: 73 KS males referred to our clinic and 73 age-matched controls underwent comprehensive measurements of anthropometry and body composition in a cross-sectional, case......-controlled study. Furthermore, genetic analysis for parental origin of the supernumerary X-chromosome, skewed X-chromosome inactivation and androgen receptor (AR) CAG repeat length was done. Main outcome measure: Anthropometry and body composition in KS and the effect of genotype hereon. Results: KS males were...

  5. Association between monoamine oxidase A gene promoter 30 bp repeat polymorphism and tardive dyskinesia in Chinese schizophrenics

    Changhe Fan; Lihua Li; Yan Fu; Hehuang Deng; Xiangjiao Liao; Youcai Zhou


    BACKGROUND: The pathophysiology of tardive dyskinesia (TD) is not yet fully understood. With the hypothesis of altered dopaminergic neurotransmission, altered activities of dopamine degrading enzymes such as monoamine oxidase A (MAOA) and their coding genes are supposed to be related to the pathophysiology of TD.OBJECTIVE: To investigate possible association between 30 bp variable number tandem repeat (VNTR) polymorphism in the promoter of MAOA gene and susceptibility, severity of neuroleptic induced TD in Chinese Han people in Guandong Province.DESIGN: Non-randomization-synchronization controlled study. SETTING: Guangdong Mental Health Institute, Guangdong Provincial People's Hospital; Guangzhou Psychiatric Hospital; Affiliated Psychiatric Hospital of Guangzhou Municipal Bureau of Civil Administration. PARTICIPANTS: A total of 179 subjects were enrolled in the study. All subjects were sporadic and genetically unrelated Chinese schizophrenic patients who were hospitalizing in Guangzhou Psychiatric Hospital or Affiliated Psychiatric Hospital of Guangzhou Municipal Bureau of Civil Administration during January to April 2005. The diagnosis of schizophrenia was made according to the criteria of Diagnostic and Statistic Manual of Mental Disorder-the third edition-revised (DSM-Ⅲ-R). Among all patients, 88 were diagnosed as with TD and 91 without TD according to the research diagnostic criteria described by Schooler-Kane. Informed consent was obtained from all subjects or their relatives.METHODS: ① TD severity was assessed with the AIMS which was a 5-degree rating scale from 0 to 4 (corresponding to none, minimal, mild, moderate and severe, respectively). The study was approved by the Ethics Committees of the two hospitals and informed consent was obtained from all subjects or their relatives. ② The polymerase chain reaction (PCR) and polyacrylamide gel electrophoresis (PAGE) techniques were used to detect MAOA gene 30 bp VNTR polymorphism in schizophrenic patients

  6. Polymorphism Profile of Nine Short Tandem Repeat Loci in the Han Chinese

    Shuangding Li; Chunxia Yan; Yajun Deng; Ruilin Wang; Jian Wang; Huanming Yang; Shengbin Li


    Nine short tandem repeat (STR) markers (D3S1358, VWA, FGA, THO1, TPOX,CSFIPO, D5S818, D13S317, and D7S820) and a sex-identification marker (Amel-ogenin locus) were amplified with multiplex PCR and were genotyped with afour-color fluorescence method in samples from 174 unrelated Han individuals inNorth China. The allele frequencies, genotype frequencies, heterozygosity, prob-ability of discrimination powers, probability of paternity exclusion and Hardy-Weinberg equilibrium expectations were determined. The results demonstratedthat the genotypes at all these STR loci in Han population conform to Hardy-Weinberg equilibrium expectations. The combined discrimination power (DP) was1.05 × 10-10 within nine STR loci analyzed and the probability of paternity exclusion(EPP) was 0.9998. The results indicate that these nine STR loci and the Amelo-genin locus are useful markers for human identification, paternity and maternitytesting and sex determination in forensic sciences.

  7. Prion octapeptide-repeat polymorphism in Polish Black-and-White cattle.

    Walawski, Krzysztof; Czarnik, Urszula


    The study was carried out in a Polish Black-and-White cattle population, represented by 167 AI sires, 200 young tested bulls, 190 bull-dams, and 606 randomly chosen cows from commercial herds. The fragment of the bovine prion protein gene (PRNP) coding the octapeptide-repeat sequence, was identified by PCR analysis. Two different gene variants of 349 bp and 373 bp in size, produced three genotypes: PRNP 6/6, PRNP 6/5 and PRNP 5/5, respectively. Allele frequency in all examined populations, on average 0.894 for PRNP 6 and 0.106 for PRNP 5, shows a significant difference between the group of cows from commercial herds, characterised by high frequency of PRNP 5 (q = 0.137) in comparison to AI sires (q = 0.077), young tested bulls (q = 0.052) and bull-dams (q = 0.084). Moreover, both analysed female groups of bull-dams and cows from commercial herds are distinguished by the presence of PRNP 5/5 homozygous animals, which were not recorded in the AI sires and young tested bulls, and had never been recognised in earlier examined Holstein-Friesian populations. Analysis of the genetic equilibrium indicates a very high conformity between observed and expected number of animals in the separate PRNP genotype groups. However, some tendency of difference is observed in highly selected cows, qualified as bull-dams on the basis of very high level of milk performance traits. PMID:12773797

  8. Genetic polymorphisms of 17 short tandem repeat loci on Y chromosome in central Croatian population.

    Gršković, Branka; Mršić, Gordan; Polašek, Ozren; Vrdoljak, Andro; Merkaš, Siniša; Anđelinović, Simun


    In forensic casework, Y-chromosome short tandem repeat (STR) haplotyping is used in human identification, paternity testing and sexual assault cases where Y-STRs provide a male-specific DNA profile. The aim of this study was to describe the genetic structure of Y chromosome in a central Croatian population. We carried out a statistical analysis of the data from previously performed genetic analyses collected during routine forensic work by the Forensic Science Centre "Ivan Vučetić". A total of 220 unrelated healthy men from central Croatia were selected for the purpose of this study. Genomic DNA was extracted using a Chelex procedure from FTA(®) cards. Y-chromosomal STRs were determined using the AmpFISTR Yfiler PCR amplification kit. The haplotype frequencies were determined by direct counting and analyzed using Arlequin 3.1 and analysis of molecular variance calculated with the Y chromosome haplotype reference database online analysis tool. A total of 212 haplotypes were identified, 204 of which were unique. Total haplotype diversity was 0.993. Locus diversity varied from 0.325 for DYS392 to 0.786 for DYS385. Discrimination capacity was 92.7%. Allele frequencies diversity was 0.615. Intermediate alleles 17.2, 18.2 and 19.2 were found at DYS458 locus. A comparison with published data for the European minimal haplotype set showed the closest relationship to the Croatian capital of Zagreb and Bosnia and Herzegovina with significant genetic distance from Slovenia and Austria. The central Croatian population is now well characterized in terms of Y-chromosome STRs, thus providing a solid basis for further forensic and genetic epidemiology studies. PMID:21279707

  9. Mismatch repair genes Mlh1 and Mlh3 modify CAG instability in Huntington's disease mice: genome-wide and candidate approaches.

    Ricardo Mouro Pinto


    Full Text Available The Huntington's disease gene (HTT CAG repeat mutation undergoes somatic expansion that correlates with pathogenesis. Modifiers of somatic expansion may therefore provide routes for therapies targeting the underlying mutation, an approach that is likely applicable to other trinucleotide repeat diseases. Huntington's disease Hdh(Q111 mice exhibit higher levels of somatic HTT CAG expansion on a C57BL/6 genetic background (B6.Hdh(Q111 than on a 129 background (129.Hdh(Q111 . Linkage mapping in (B6x129.Hdh(Q111 F2 intercross animals identified a single quantitative trait locus underlying the strain-specific difference in expansion in the striatum, implicating mismatch repair (MMR gene Mlh1 as the most likely candidate modifier. Crossing B6.Hdh(Q111 mice onto an Mlh1 null background demonstrated that Mlh1 is essential for somatic CAG expansions and that it is an enhancer of nuclear huntingtin accumulation in striatal neurons. Hdh(Q111 somatic expansion was also abolished in mice deficient in the Mlh3 gene, implicating MutLγ (MLH1-MLH3 complex as a key driver of somatic expansion. Strikingly, Mlh1 and Mlh3 genes encoding MMR effector proteins were as critical to somatic expansion as Msh2 and Msh3 genes encoding DNA mismatch recognition complex MutSβ (MSH2-MSH3. The Mlh1 locus is highly polymorphic between B6 and 129 strains. While we were unable to detect any difference in base-base mismatch or short slipped-repeat repair activity between B6 and 129 MLH1 variants, repair efficiency was MLH1 dose-dependent. MLH1 mRNA and protein levels were significantly decreased in 129 mice compared to B6 mice, consistent with a dose-sensitive MLH1-dependent DNA repair mechanism underlying the somatic expansion difference between these strains. Together, these data identify Mlh1 and Mlh3 as novel critical genetic modifiers of HTT CAG instability, point to Mlh1 genetic variation as the likely source of the instability difference in B6 and 129 strains and suggest

  10. Genetic polymorphism of the 26 short tandem repeat loci in the Chinese Hebei Han population using two commercial forensic kits.

    Lei, Liang; Xu, Jie; Du, Qingqing; Fu, Lihong; Zhang, Xiaojing; Yu, Feng; Ma, Chunling; Cong, Bin; Li, Shujin


    We determined the allele frequencies and forensic parameters for the 26 short tandem repeat (STR) autosomal markers in two commercial kits (the Investigator HDplex and AmpFLSTR(®) Identifiler(®) systems) for 183 unrelated individuals from the Han population of the Hebei Province of China. The 26 STRs were all in Hardy-Weinberg equilibrium. No linkage disequilibrium was detected between any pair of loci. The combined power of discrimination and the combined power of exclusion for the 26 STR loci were 1-7.74E-31 and 1-1.21E-11, respectively. Six rare alleles of D10S2325 were identified and named 20, 21, 22, 23, 24, and 31. All the length of the six rare alleles were out of the range of allelic ladder. We calculated the population pairwise genetic distance based on the allele frequencies, using published population data including German, central Polish, south Dutch, northeastern Polish, south Brazilian, Korean, Sichuan Han of China, and Shanghai Han of China. Also we examined the population pairwise genetic distance of loci included in Identifiler system between Hebei Han and other ethnic population of China. These 26 autosomal STR loci could provide highly informative polymorphic data for paternity testing and forensic identification in the Hebei Han population in China. Because they are all in linkage equilibrium, they could be used together to solve deficient kinship cases or cases with mutations. PMID:25262358

  11. Size polymorphism of chicken major histocompatibility complex-encoded B-G molecules is due to length variation in the cytoplasmic heptad repeat region

    Kaufman, J; Salomonsen, J; Skjødt, K;


    , which bear intrachain disulfide bonds. All 3-6 bands have different mobilities in SDS gels between different haplotypes, ranging from 30 to 55 kDa. This size polymorphism is not affected by glycosidase treatment or addition of protease inhibitors. Partial proteolysis of cell surface-iodinated B...... that the extracellular regions of these molecules are very similar and that the length polymorphism is due to variations in the cytoplasmic regions. Inspection of the cDNA-derived protein sequence in this region shows many heptad repeats, which may allow variation in length by step deletion and alternative splicing...

  12. The serotonin transporter gene linked polymorphic region is associated with the behavioral response to repeated stress exposure in infant rhesus macaques

    Spinelli, Simona; Schwandt, Melanie L.; Lindell, Stephen G.; Heilig, Markus; Stephen J. Suomi; Higley, J. Dee; Goldman, David; Barr, Christina S.


    The short allele of the serotonin transporter linked polymorphic region (5-HTTLPR) moderates the effects of stress on vulnerability to mood and anxiety disorders. The mechanism by which this occurs may relate to differential sensitivity to stressful life events. Here we explored whether 5-HTTLPR and sex affected behavioral responses to repeated maternal separation in infant rhesus macaques. Behaviors were collected during the acute (Day 1) and the chronic (Days 2–4) phases of the separation, ...

  13. Genetic polymorphisms of short tandem repeat loci D13S305, D13S631 and D13S634 in the Han population of Tianjin, China

    SHI, YUNFANG; LI, XIAOZHOU; JU, DUAN; Li, Yan; Zhang, Xiuling; Zhang, Ying


    Short tandem repeat (STR) markers, also known as microsatellites, are extensively used in mapping studies, forensics and disease diagnosis due to their small dimension and low mutation and high polymorphism rates. In recent years quantitative fluorescence polymerase chain reaction (QF-PCR) has been successfully used to amplify STR markers in the prenatal diagnosis of common chromosomal abnormalities. This method provides a diagnosis of common aneuploidies 24–48 h after sampling with low error...

  14. Genotyping of the Helicobacter pylori cagA Gene Isolated From Gastric Biopsies in Shiraz, Southern Iran: A PCR-RFLP and Sequence Analysis Approach

    Moaddeb, Afsaneh; Fattahi, Mohammad Reza; Firouzi, Roya; Derakhshandeh, Abdollah; Farshad, Shohreh


    Background Cytotoxin-associated gene A (cagA) is an important virulence factor in the pathogenesis of Helicobacter pylori. Objectives The aim of this study was to genotype the H. pylori cagA gene isolated from antral biopsies of patients with stomach symptoms, using a PCR-restriction fragment length polymorphism (PCR-RFLP) analysis. Patients and Methods A total of 161 gastric biopsies were collected from patients with stomach symptoms. After isolation of H. pylori from the biopsy culture, the...

  15. Preliminary evidence for an association of a dinucleotide repeat polymorphism at the MAOA gene with early onset alcoholism/substance abuse

    Vanyukov, M.M.; Moss, H.B.; Tarter, R.E. [Univ. of Pittsburg, PA (United States)] [and others


    An association between the liability to early onset alcoholism/substance abuse and a recently discovered dinucleotide repeat length polymorphism at the MAOA gene (MAOCA-1) was examined using polymerase chain reaction (PCR). A significant correlation between the presence/absence of the disorder and the length of the MAOCA-1 repeat was found in males, but not females, with {open_quotes}long{close_quotes} alleles (repeat length above 115 bp) associated with both increased risk for the disorder and lower age of onset of substance abuse. These preliminary data suggest that further exploration of the relationship between the MAOA gene and behavioral traits in an expanded sample is warranted. 22 refs., 1 fig., 3 tabs.

  16. IL1 receptor antagonist gene IL1-RN variable number of tandem repeats polymorphism and cancer risk: a literature review and meta-analysis.

    Ying Zhang

    Full Text Available IL1 receptor antagonist (IL1RA and IL1beta (IL1β, members of the pro-inflammatory cytokine interleukin-1 (IL1 family, play a potential role against infection and in the pathogenesis of cancers. The variable number of tandem repeats (VNTR polymorphism in the second intron of the IL1 receptor antagonist gene (IL1-RN and a polymorphism in exon 5 of IL1B (IL1B+3954C>T, rs1143634 have been suggested in predisposition to cancer risk. However, studies have shown inconsistent results. To validate any association, a meta-analysis was performed with 14,854 cases and 19,337 controls from 71 published case-control studies for IL1-RN VNTR and 33 eligible studies contained 7,847 cases and 8917 controls for IL1B +3954. Odds ratios (ORs with 95% confidence intervals (CIs were calculated from comparisons to assess the strength of the association. There was significant association between the IL1-RN VNTR polymorphism and the risk of cancer for any overall comparison. Furthermore, cancer type stratification analysis revealed that there were significantly increased risks of gastric cancer, bladder cancer and other cancer groups. Infection status analysis indicated that the H. pylori or HBV/HCV infection and IL1-RN VNTR genotypes were independent factors for developing gastric or hepatocellular cancers. In addition, a borderline significant association was observed between IL1B+3954 polymorphism and the increased cancer risk. Although some modest bias could not be eliminated, this meta-analysis suggested that the IL1-RN VNTR polymorphisms may contribute to genetic susceptibility to gastric cancer. More studies are needed to further evaluate the role of the IL1B+3954 polymorphism in the etiology of cancer.

  17. Hsp90 modulates CAG repeat instability in human cells

    Mittelman, David; Sykoudis, Kristen; Hersh, Megan; Lin, Yunfu; Wilson, John H.


    The Hsp90 molecular chaperone has been implicated as a contributor to evolution in several organisms by revealing cryptic variation that can yield dramatic phenotypes when the chaperone is diverted from its normal functions by environmental stress. In addition, as a cancer drug target, Hsp90 inhibition has been documented to sensitize cells to DNA-damaging agents, suggesting a function for Hsp90 in DNA repair. Here we explore the potential role of Hsp90 in modulating the stability of nucleoti...

  18. The CFTR polymorphisms poly-T, TG-repeats and M470V in Chinese males with congenital bilateral absence of the vas deferens

    Wu-Hua Ni; Lei Jiang; Qian-Jin Fei; Jian-Yuan Jin; Xu Yang; Xue-Feng Huang


    Congenital bilateral absence of the vas deferens (CBAVD) is a frequent cause of obstructive azoospermia,and mutations of the cystic fibrosis transmembrane conductance regulator (CFTR) gene have also been frequently identified in patients with CBAVD.However,the distribution of the CFTR polymorphisms M470V,poly-T,TG-repeats and F508del mutation in the Chinese CBAVD population with presumed low cystic fibrosis (CF) frequency remains to be evaluated.Samples obtained from 109 Chinese infertile males with CBAVD and 104 normal controls were analyzed for the presence of CFTR (TG)m(T)n,M470V and F508del by PCR amplification followed by direct sequencing.Our study showed that the F508del mutation was not found in our patients.The 5T mutation was present with high frequency in Chinese CBAVD patients and IVS8-5T linked to either 12 or 13 TG repeats was highly prevalent among CBAVD patients (97.22% of 72 cases and 96.91% of 97 alleles with IVS8-5T).Moreover,a statistically significant relationship between TG12-5T-V470 haplotype and CBAVD was detected.This study indicated that the CFTR polymorphisms poly-T,TG-repeats and M470V might affect the process of CBAVD in the Chinese population.

  19. Comparative analysis of common CFTR polymorphisms poly-T, TG-repeats and M470V in a healthy Chinese population

    Qin Huang; Wei Ding; Mu-Xin Wei


    AIM: To investigate the three important cystic fibrosis transmembrane conductance regulator (CFTR) haplotypes po!y-T, TG-repeats and the M470V polymorphisms in the Chinese population, and to compare their distribution with that in Caucasians and other Asian populations.METHODS: Genomic DNA was extracted from blood leukocytes. Exons 9 and 10 of the CFTR gene were obtained through polymerase chain reaction (PCR). Exon 9 DNA sequences were directly detected by an automated sequencer and poly-T and TG-repeats were identified by direct sequence analysis. Pure exon 10 PCR-amplified products were digested by Hph I restriction enzyme and the M470V mutation was detected by the AGE photos of digestion products.RESULTS: T7 was the most common (93.6%) haplotype and the (TG)ll frequency of 57.2% and (TG)12 frequency of 40.9% were dominant haplotypes in the junction of intron 8 (IVS-8) and exon 9. The frequency of T5 was 3.8% and all T5 allele tracts (10 alleles) were joined with (TG)12. Four new alleles of T6 (1.5%) were found in three healthy individuals. In exon 10, the V allele (56.1%) was slightly more frequent than the M allele (43.9%), and the M/V (45.5%) was the dominant genotype in these individuals. The three major haplotypes T7-(TG)ll-V470, T7-(TG)12-M470 and T7-TG11-M470 were related to nearly 86.0% of the population.CONCLUSION: The polymorphisms of poly-T, TG-repeats, and M470V distribution were similar to those in other East Asians, but they had marked differences in frequency from those single haplotype polymorphisms or linkage haplotypes in Caucasians. Thus, they may be able to explain the low incidence of CF and CF-like diseases in Asians.

  20. Study of the Cytoxin-Associated Gene A (CagA Gene) in Helicobacter pylori Using Gastric Biopsies of Iraqi Patients

    Kalaf, Elham A.; Zahra M Al-Khafaji; Nahi Y Yassen; AL-Abbudi, Fadel A.; Sadwen, Saad N.


    Background and Aims: The Helicobacter pylori CagA gene is a major virulence factor that plays an important role in gastric pathologies. The size variation of CagA gene, which is dependent on the 3′ repeat region, contains one or more Glu-Pro-Ile-Tyr-Ala (EPIYA) motifs and CagA multimerization (CM) motifs. Four segments flanking the EPIYA motifs, EPIYA −A, −B, −C, or −D, were reported to play a crucial role in the pathogenesis of H. pylori infection. The aim was to determine the roles of EPIYA...

  1. Characterization of the patterns of polymorphism in a [open quotes]cryptic repeat[close quotes] reveals a novel type of hypervariable sequence

    Jacobson, D.P.; Schmeling, P.; Sommer, S.S. (Mayo Clinic/Foundation, Rochester, MN (United States))


    Alternating purine and pyrimidine repeats (RY(i)) are an abundant source of polymorphism. The subset with long tandem repeats of GT or AC (GT(i)) have been studied extensively, but cryptic RY(i) (i.e., no single tandem repeat predominates) have received little attention. The factor IX gene has a polymorphic cryptic RY(i) of 142-216 bp. Previously, there were four known polymorphic alleles, of the form AB, A[sub 2]B, A[sub 2]B[sub 2], and A[sub 3]B[sub 2], where A = (GT)(AC)[sub 3](AT)[sub 3](GT)(AT)[sub 4] and B = A with an additional 3' AT dinucleotide. To further characterize this locus, the authors examined more than 1,700 additional human chromosomes and determined the sequences of the homologous sites in orangutans and chimpanzees. The novel alleles found in humans expand the repertoire of A/B alleles to A[sub 0-4]B[sub 1] and A[sub 1-3]B[sub 2]. The A[sub n]B[sub 2] series are abundant in Caucasians but are absent in blacks and Asians. Conversely, the A[sub 0]B[sub 1] allele is common in blacks but is not found in more than 1,700 Caucasian chromosomes. The data are compatible with a model in which recombination is more frequent than polymerase slippage at this locus. In orangutans, the RY(i) is present, but the sequence is markedly different. An A/B-type of pattern was discerned in which B differs from A by an additional six (AT) dinucleotides at the 3' end. In chimpanzees, the size of the RY(i) locus was greatly expanded, and the sequence showed a novel pattern of hypervariability in which there are many tandem repeats of the form (GT)[sub n](AC)[sub 0](AT)[sub p](GT)[sub q](AT)[sub s], where n, o, p, q, and s are different integers. The sequences of the factor IX intron 1 cryptic RY(i) in three primates provide perspective on the range of possible patterns of polymorphism. Analysis of the patterns suggests how the RY(i) can be conserved during evolution, while the precise sequence varies. 25 refs., 5 figs., 3 tabs.

  2. Variable number of tandem repeat polymorphisms of the interleukin-1 receptor antagonist gene IL-1RN: a novel association with the athlete status

    Ryckman Kelli K


    Full Text Available Abstract Background The interleukin-1 (IL-1 family of cytokines is involved in the inflammatory and repair reactions of skeletal muscle during and after exercise. Specifically, plasma levels of the IL-1 receptor antagonist (IL-1ra increase dramatically after intense exercise, and accumulating evidence points to an effect of genetic polymorphisms on athletic phenotypes. Therefore, the IL-1 family cytokine genes are plausible candidate genes for athleticism. We explored whether IL-1 polymorphisms are associated with athlete status in European subjects. Methods Genomic DNA was obtained from 205 (53 professional and 152 competitive non-professional Italian athletes and 458 non-athlete controls. Two diallelic polymorphisms in the IL-1β gene (IL-1B at -511 and +3954 positions, and a variable number tandem repeats (VNTR in intron 2 of the IL-1ra gene (IL-1RN were assessed. Results We found a 2-fold higher frequency of the IL-1RN 1/2 genotype in athletes compared to non-athlete controls (OR = 1.93, 95% CI = 1.37-2.74, 41.0% vs. 26.4%, and a lower frequency of the 1/1 genotype (OR = 0.55, 95% CI = 0.40-0.77, 43.9% vs. 58.5%. Frequency of the IL-1RN 2/2 genotype did not differ between groups. No significant differences between athletes and controls were found for either -511 or +3954 IL-1B polymorphisms. However, the haplotype (-511C-(+3954T-(VNTR2 was 3-fold more frequent in athletes than in non-athletes (OR = 3.02, 95% CI = 1.16-7.87. Interestingly, the IL-1RN 1/2 genotype was more frequent in professional than in non-professional athletes (OR = 1.92, 95% CI = 1.02-3.61, 52.8% vs. 36.8%. Conclusions Our study found that variants at the IL-1ra gene associate with athletic status. This confirms the crucial role that cytokine IL-1ra plays in human physical exercise. The VNTR IL-1RN polymorphism may have implications for muscle health, performance, and/or recovery capacities. Further studies are needed to assess these specific issues. As VNTR IL-1RN

  3. Allelic ladder characterization of the short tandem repeat polymorphism located in the 5{prime} flanking region to the human coagulation factor XIII A subunit gene

    Puers, C. [Promega Corp., Madison, WI (United States)]|[Institute for Forensic Medicine, Muenster (Germany); Lins, A.M.; Sprecher, C.J. [Promega Corp., Madison, WI (United States)] [and others


    The short tandem repeat (STR) polymorphism present within the 5{prime} untranslated region of the human coagulation factor XIII A subunit gene, HUM-F13A01 [AAAG]{sub n}, was evaluated using an allelic ladder, i.e., a standard size marker consisting of amplified alleles from the locus. The allelic ladder was constructed by pooling 12 polymerase chain reaction (PCR)-amplified alleles identified by their differential migration in denaturing polyacrylamide gel electrophoresis. This standard marker was used to distinguish 14 different alleles observed at this locus. Sequence analyses indicate that 13 of the alleles contain 4 through 16 iterations of the tandemly repeated AAAG sequence, respectively. The remaining allele carries four repeats and displays a deletion of two consecutive nucleotides (GT), one base distal to the repeat region. The allelic ladder was employed to type 326 F13A01 chromosomes rapidly and reliably in representatives of a German Caucasian population. Population data were analyzed with respect to Hardy-Weinberg Equilibrium (HWE) and compared with those of a previously studied Houston, Texas, Caucasian population. 27 refs., 2 figs., 1 tab.

  4. Efficient screening of long terminal repeat retrotransposons that show high insertion polymorphism via high-throughput sequencing of the primer binding site.

    Monden, Yuki; Fujii, Nobuyuki; Yamaguchi, Kentaro; Ikeo, Kazuho; Nakazawa, Yoshiko; Waki, Takamitsu; Hirashima, Keita; Uchimura, Yosuke; Tahara, Makoto


    Retrotransposons have been used frequently for the development of molecular markers by using their insertion polymorphisms among cultivars, because multiple copies of these elements are dispersed throughout the genome and inserted copies are inherited genetically. Although a large number of long terminal repeat (LTR) retrotransposon families exist in the higher eukaryotic genomes, the identification of families that show high insertion polymorphism has been challenging. Here, we performed an efficient screening of these retrotransposon families using an Illumina HiSeq2000 sequencing platform with comprehensive LTR library construction based on the primer binding site (PBS), which is located adjacent to the 5' LTR and has a motif that is universal and conserved among LTR retrotransposon families. The paired-end sequencing library of the fragments containing a large number of LTR sequences and their insertion sites was sequenced for seven strawberry (Fragaria × ananassa Duchesne) cultivars and one diploid wild species (Fragaria vesca L.). Among them, we screened 24 families with a "unique" insertion site that appeared only in one cultivar and not in any others, assuming that this type of insertion should have occurred quite recently. Finally, we confirmed experimentally the selected LTR families showed high insertion polymorphisms among closely related cultivars. PMID:25072847

  5. Genetic relationships and evolution in Cucurbita pepo (pumpkin, squash, gourd) as revealed by simple sequence repeat polymorphisms

    Gong, Li; Paris, Harry S.; Nee, Michael H.; Stift, Gertraud; Pachner, Martin; Vollmann, Johann; Lelley, Tamas


    Genetic relationships among 104 accessions of Cucurbita pepo were assessed from polymorphisms in 134 SSR (microsatellite) and four SCAR loci, yielding a total of 418 alleles, distributed among all 20 linkage groups. Genetic distance values were calculated, a dendrogram constructed, and principal coordinate analyses conducted. The results showed 100 of the accessions as distributed among three clusters representing each of the recognized subspecies, pepo, texana, and fraterna. The remaining fo...

  6. Analysis of Short Tandem Repeat and Single Nucleotide Polymorphism Loci From Single-Source Samples Using a Custom HaloPlex Target Enrichment System Panel.

    Wendt, Frank R; Zeng, Xiangpei; Churchill, Jennifer D; King, Jonathan L; Budowle, Bruce


    Short tandem repeats and single nucleotide polymorphisms (SNPs) are used to individualize biological evidence samples. Short tandem repeat alleles are characterized by size separation during capillary electrophoresis (CE). Massively parallel sequencing (MPS) offers an alternative that can overcome limitations of the CE. With MPS, libraries are prepared for each sample, entailing target enrichment and bar coding, purification, and normalization. The HaloPlex Target Enrichment System (Agilent Technologies) uses a capture-based enrichment system with restriction enzyme digestion to generate fragments containing custom-selected markers. It offers another possible workflow for typing reference samples. Its efficacy was assessed using a panel of 275 human identity SNPs, 88 short tandem repeats, and amelogenin. The data analyzed included locus typing success, depth of sequence coverage, heterozygote balance, and concordance. The results indicate that the HaloPlex Target Enrichment System provides genetic data similar to that obtained by conventional polymerase chain reaction-CE methods with the advantage of analyzing substantially more markers in 1 sequencing run. The genetic typing performance of HaloPlex is comparable to other MPS-based sample preparation systems that utilize primer-based target enrichment. PMID:27075592

  7. Chemical correction of pre-mRNA splicing defects associated with sequestration of muscleblind-like 1 protein by expanded r(CAG)-containing transcripts.

    Kumar, Amit; Parkesh, Raman; Sznajder, Lukasz J; Childs-Disney, Jessica L; Sobczak, Krzysztof; Disney, Matthew D


    Recently, it was reported that expanded r(CAG) triplet repeats (r(CAG)(exp)) associated with untreatable neurological diseases cause pre-mRNA mis-splicing likely due to sequestration of muscleblind-like 1 (MBNL1) splicing factor. Bioactive small molecules that bind the 5'CAG/3'GAC motif found in r(CAG)(exp) hairpin structure were identified by using RNA binding studies and virtual screening/chemical similarity searching. Specifically, a benzylguanidine-containing small molecule was found to improve pre-mRNA alternative splicing of MBNL1-sensitive exons in cells expressing the toxic r(CAG)(exp). The compound was identified by first studying the binding of RNA 1 × 1 nucleotide internal loops to small molecules known to have affinity for nucleic acids. Those studies identified 4',6-diamidino-2-phenylindole (DAPI) as a specific binder to RNAs with the 5'CAG/3'GAC motif. DAPI was then used as a query molecule in a shape- and chemistry alignment-based virtual screen to identify compounds with improved properties, which identified 4-guanidinophenyl 4-guanidinobenzoate, a small molecule that improves pre-mRNA splicing defects associated with the r(CAG)(exp)-MBNL1 complex. This compound may facilitate the development of therapeutics to treat diseases caused by r(CAG)(exp) and could serve as a useful chemical tool to dissect the mechanisms of r(CAG)(exp) toxicity. The approach used in these studies, defining the small RNA motifs that bind small molecules with known affinity for nucleic acids and then using virtual screening to optimize them for bioactivity, may be generally applicable for designing small molecules that target other RNAs in the human genomic sequence. PMID:22252896

  8. Polymorphisms in leucine-rich repeat genes are associated with autism spectrum disorder susceptibility in populations of European ancestry

    Sousa Inês; Clark Taane G; Holt Richard; Pagnamenta Alistair T; Mulder Erik J; Minderaa Ruud B; Bailey Anthony J; Battaglia Agatino; Klauck Sabine M; Poustka Fritz; Monaco Anthony P


    Abstract Background Autism spectrum disorders (ASDs) are a group of highly heritable neurodevelopmental disorders which are characteristically comprised of impairments in social interaction, communication and restricted interests/behaviours. Several cell adhesion transmembrane leucine-rich repeat (LRR) proteins are highly expressed in the nervous system and are thought to be key regulators of its development. Here we present an association study analysing the roles of four promising candidate...

  9. CagA-mediated pathogenesis of Helicobacter pylori.

    Tohidpour, Abolghasem


    Helicobacter pylori has been described as the main etiologic agent of gastric cancer, causing a considerable rate of mortality and morbidity in human population across the world. Although the infection mainly begins asymptomatically, but simply develops to peptic ulcer, chronic gastritis, lymphoma of the gastric mucosa and eventually adenocarcinoma. The major pathological feature of H. pylori infection is due to the activity of the cytotoxin-associated gene A (CagA), a 125-140 kDa protein encoded by the cag pathogenicity island (cagPAI). CagA is also known as the first bacterial onco-protein, ranking the H. pylori-mediated adenocarcinoma as the second most deadly cancer type worldwide. Upon cytoplasmic translocation CagA undergoes interacting with numerous proteins in phosphorylation dependant and independent manners within the gastric epithelial cells. The profound effect of CagA on multiple intracellular pathways causes major consequences such as perturbation of intracellular actin trafficking, stimulation of inflammatory responses and disruption of cellular tight junctions. Such activities of CagA further participate in development of the hummingbird phenotype and gastric cancer. This review is sought to provide a structural and functional analysis of the CagA protein with focus on demonstrating the molecular basis of the mechanism of CagA intracellular translocation and its interaction with intracellular targets. PMID:26796299

  10. [The role of CagA in H. pylori infection].

    Tanaka, Hiroshi; Yoshida, Masaru; Azuma, Takeshi


    Helicobacter pylori (H. pylori) chronically colonizes human gastric epithelium and induces various diseases. But the mechanism of carcinogenesis in H. pylori infection remains to be assessed. We described that after attachment of H. pylori to gastric epithelial cells, CagA is injected directly from the bacteria into the cells and undergoes tyrosine phosphorylation. Tyrosine phosphorylated CagA can bind to SHP-2. Deregulation of SHP -2 by CagA may induce abnormal proliferation and movement of gastric epithelial cells. There are two patterns of CagA motifs between East Asian strains and Western strains. East Asian-type CagA confers stronger SHP-2 binding and transforming activities than Western-type CagA. We assessed the association between CagA diversity and clinical outcome in Asian countries, where mortalities from gastric cancer is different. As results, H. pylori infection with East Asian-type CagA was associated with gastric atrophy and cancer. Therefore, persistent active inflammation induced by the East Asian CagA-positive strain may play a role in the pathogenesis of disease. PMID:19999107

  11. DNA polymorphisms in cuban varieties of avocado (persea americana mill.) as detected by inverse sequence tagged repeat (ISTR) analysis

    A survey of the genetic diversity among commercial Cuban avocado varieties was initiated using ISTR analysis. ISTR markers were efficient in detecting polymorphisms among the genotypes. The obtained dissimilarities values ranged from 0.24 between var. Suardia and Hass to 1.00 between Lula and Los Moros or CHI-3 with an average dissimilarity of 0.78. A cluster analysis was performed based on dissimilarity using UPGMA as the clustering method. The efficiency of UPGMA in estimating genetic relationships between varieties was corroborated by the cophenetic correlation coefficients, which indicated that the distortion degree in the relationship of the estimated dissimilarities was minimal. Ecological groups were not adequately represented in the dendrogram. Thus, West Indians, Guatemalan and Mexican genotypes were positioned across the dendrogram. The utility of ISTR for genotype identification and assessment of genetic diversity in commercial avocado varieties is discussed

  12. Analysis of coding-polymorphisms in NOTCH-related genes reveals NUMBL poly-glutamine repeat to be associated with schizophrenia in Brazilian and Danish subjects

    Passos Gregorio, Sheila; Gattaz, Wagner F; Tavares, Hildeberto;


    regarding their possible involvement in schizophrenia. In the present study we investigated the link of non-synonymous variants of five genes of the Notch pathway (NOTCH2, NOTCH3, JAGGED2, ASCL1 and NUMBL) to schizophrenia in a group of 200 Brazilian patients and 200-paired controls. Also, we replicated the...... association of the NUMBL variant, our most promising finding, in an unrelated set of 684 Danish patients and controls. When the Brazilian and Danish cohorts were merged, a total of 1084 subjects, we found the allele 18 CAG of NUMBL (p=0.003, x2=8.88, OR=1.30, 95% CI 1.09-1.56) as well as the 18/18 CAG...

  13. Genetic relationships and evolution in Cucurbita pepo (pumpkin, squash, gourd) as revealed by simple sequence repeat polymorphisms.

    Gong, Li; Paris, Harry S; Nee, Michael H; Stift, Gertraud; Pachner, Martin; Vollmann, Johann; Lelley, Tamas


    Genetic relationships among 104 accessions of Cucurbita pepo were assessed from polymorphisms in 134 SSR (microsatellite) and four SCAR loci, yielding a total of 418 alleles, distributed among all 20 linkage groups. Genetic distance values were calculated, a dendrogram constructed, and principal coordinate analyses conducted. The results showed 100 of the accessions as distributed among three clusters representing each of the recognized subspecies, pepo, texana, and fraterna. The remaining four accessions, all having very small, round, striped fruits, assumed central positions between the two cultivated subspecies, pepo and texana, suggesting that they are relicts of undescribed wild ancestors of the two domesticated subspecies. In both, subsp. texana and subsp. pepo, accessions belonging to the same cultivar-group (fruit shape) associated with one another. Within subsp. pepo, accessions grown for their seeds or that are generalists, used for both seed and fruit consumption, assumed central positions. Specialized accessions, grown exclusively for consumption of their young fruits, or their mature fruit flesh, or seed oil extraction, tended to assume outlying positions, and the different specializations radiated outward from the center in different directions. Accessions of the longest-fruited cultivar-group, Cocozelle, radiated bidirectionally, indicating independent selection events for long fruits in subsp. pepo probably driven by a common desire to consume the young fruits. Among the accessions tested, there was no evidence for crossing between subspecies after domestication. PMID:22101929

  14. Relevance of MUC1 mucin variable number of tandem repeats polymorphism in H pylori adhesion to gastric epithelial cells

    Natália R Costa; Nuno Mendes; Nuno T Marcos; Celso A Reis; Thomas Caffrey; Michael A Hollingsworth; Filipe Santos-Silva


    AIM:To evaluate the influence of MUC1 mucin variable number of tandem repeats (VNTR) variability on H pylori adhesion to gastric cells.METHODS:Enzyme linked immunosorbent assay (ELISA)-based adhesion assays were performed to measure the adhesion of different H pylori strains (HP26695 and HPTx30a) to gastric carcinoma cell lines (GP202 and MKN45) and GP202 clones expressing recombinant MUC1 with different VNTR lengths.RESULTS:Evaluation of adhesion results shows that H pylori pathogenic strain HP26695 has a significantly higher (P<0.05) adhesion to all the cell lines and clones tested,when compared to the non-pathogenic strain HPTx30a.Bacteria showed a significantly higher (P<0.05)adhesion to the GP202 cell line,when compared to the MKN45 cell line.Furthermore,both strains showed a significantly higher (P<0.05) adhesion to GP202 clones with larger MUC1 VNTR domains.CONCLUSION:This work shows that MUC1 mucin variability conditions H pylori binding to gastric cells.The extent of bacterial adhesion depends on the size of the MUC1 VNTR domain.The adhesion is further dependent on bacterial pathogenicity and the gastric cell line.MUC1 mucin variability may contribute to determine H pylori colonization of the gastric mucosa.

  15. [open quotes]Cryptic[close quotes] repeating triplets of purines and pyrimidines (cRRY(i)) are frequent and polymorphic: Analysis of coding cRRY(i) in the proopiomelanocortin (POMC) and TATA-binding protein (TBP) genes

    Gostout, B.; Qiang Liu; Sommer, S.S. (Mayo Clinic/Foundation, Rochester, MN (United States))


    Triplets of the form of purine, purine, pyrimidine (RRY(i)) are enhanced in frequency in the genomes of primates, rodents, and bacteria. Some RRY(i) are [open quotes]cryptic[close quotes] repeats (cRRY(i)) in which no one tandem run of a trinucleotide predominates. A search of human GenBank sequence revealed that the sequences of cRRY(i) are highly nonrandom. Three randomly chosen human cRRY(i) were sequenced in search of polymorphic alleles. Multiple polymorphic alleles were found in cRRY(i) in the coding regions of the genes for proopiomelanocortin (POMC) and TATA-binding protein (TBP). The highly polymorphic TBP cRRY(i) was characterized in detail. Direct sequencing of 157 unrelated human alleles demonstrated the presence of 20 different alleles which resulted in 29--40 consecutive glutamines in the amino-terminal region of TBP. These alleles are differently distributed among the races. PCR was used to screen 1,846 additional alleles in order to characterize more fully the range of variation in the population. Three additional alleles were discovered, but there was no example of a substantial sequence amplification as is seen in the repeat sequences associated with X-linked spinal and bulbar muscular atrophy, myotonic dystrophy, or the fragile-X syndrome. The structure of the TBP cRRY(i) is conserved in the five monkey species examined. In the chimpanzee, examination of four individuals revealed that the cRRY(i) was highly polymorphic, but the pattern of polymorphism differed from that in humans. The TBP cRRY(i) displays both similarities with and differences from the previously described RRY(i) in the coding sequence of the androgen receptor. The data suggest how simple tandem repeats could evolve from cryptic repeats. 18 refs., 3 figs., 6 tabs.

  16. Genetic and physical mapping of 2q35 in the region of NRAMP and IL8R genes: Identification of a polymorphic repeat in exon 2 of NRAMP

    White, J.K.; Shaw, M.A.; Barton, C.H. [Addenbrooke`s Hospital, Cambridge (United Kingdom)] [and others


    Recent interest has focused on the region of conserved synteny between mouse chromosome 1 and human 2q33-q37, particularly over the region encoding the murine macrophage resistance gene Ity/Lsh/Bcg (candidate Nramp) and members of the Il8r interleukin-8 (IL8) receptor gene cluster. In this paper, identification of a restriction fragment length polymorphism in the Il8RB gene in 35 pedigrees previously typed for markers in the 2q33-37 interval provided evidence (lod scores > 3) for linkage between Il8RB and the 2q34-135 markers FN1, TNP1, VIL1, and DES. Physical mapping, using yeast artificial chromosomes isolated with VIL1, confirmed that IL8RA, IL8RB and the IL8RB pseudogene map within the NRAMP-VIL1 interval, with the physical distance (155 kb) from 5{prime} LSH to 3{prime} VIL1 representing {approx}3-fold that observed in the mouse. Partial sequencing of NRAMP confirmed the presence of the N-terminal proline/serine-rich putative SH3 binding domain in exon 2 of the human gene. Further analysis of Brazilian leprosy and visceral leishmaniasis pedigrees identified a rare second allele varying in a 9-nucleotide repeat motif of the exon 2 sequence but segregating independently of the disease phenotype. 38 refs., 4 figs., 3 tabs.

  17. Clustering of Beijing genotype Mycobacterium tuberculosis isolates from the Mekong delta in Vietnam on the basis of variable number of tandem repeat versus restriction fragment length polymorphism typing

    Huyen Mai NT


    Full Text Available Abstract Background In comparison to restriction fragment length polymorphism (RFLP typing, variable number of tandem repeat (VNTR typing is easier to perform, faster and yields results in a simple, numerical format. Therefore, this technique has gained recognition as the new international gold standard in typing of Mycobacterium tuberculosis. However, some reports indicated that VNTR typing may be less suitable for Beijing genotype isolates. We therefore compared the performance of internationally standardized RFLP and 24 loci VNTR typing to discriminate among 100 Beijing genotype isolates from the Southern Vietnam. Methods Hundred Beijing genotype strains defined by spoligotyping were randomly selected and typed by RFLP and VNTR typing. The discriminatory power of VNTR and RFLP typing was compared using the Bionumerics software. Results Among 95 Beijing strains available for analysis, 14 clusters were identified comprising 34 strains and 61 unique profiles in 24 loci VNTR typing ((Hunter Gaston Discrimination Index (HGDI = 0.994. 13 clusters containing 31 strains and 64 unique patterns in RFLP typing (HGDI = 0.994 were found. Nine RFLP clusters were subdivided by VNTR typing and 12 VNTR clusters were split by RFLP. Five isolates (5% revealing double alleles or no signal in two or more loci in VNTR typing could not be analyzed. Conclusions Overall, 24 loci VNTR typing and RFLP typing had similar high-level of discrimination among 95 Beijing strains from Southern Vietnam. However, loci VNTR 154, VNTR 2461 and VNTR 3171 had hardly added any value to the level of discrimination.

  18. Structural basis for triplet repeat disorders

    Baldi, Pierre; Brunak, Søren; Chauvin, Yves; Pedersen, Anders Gorm


    ? Results: Using several different computational models of DNA structure, we show that the triplets involved in the pathological repeats generally fall into extreme classes. Thus, CAG/CTG repeats are particularly flexible, whereas GCC, CGG and GAA repeats appear to display both flexible and rigid (but...... curved) characteristics depending on the method of analysis. The fact that (1) trinucleotide repents often become increasingly unstable when they exceed a length of approximately 50 repeats, and (2) repented 12-mers display a similar increase in instability above 13 repeats, together suggest that......, which we predict to have very high flexibility, may play a role in the pathogenesis of the neurodegenerative disorder multiple system atrophy (MSA)....

  19. Psychiatric and cognitive symptoms in Huntington's disease are modified by polymorphisms in catecholamine regulating enzyme genes.

    Vinther-Jensen, T; Nielsen, T T; Budtz-Jørgensen, E; Larsen, I U; Hansen, M M; Hasholt, L; Hjermind, L E; Nielsen, J E; Nørremølle, A


    Huntington's disease (HD) is an autosomal dominantly inherited neurodegenerative disorder characterized by motor, psychiatric, and cognitive manifestations. HD is caused by a CAG repeat expansion in the Huntingtin (HTT) gene but the exact pathogenesis remains unknown. Dopamine imbalance has previously been shown in HD, and furthermore dopamine is thought to be implicated in cognition, behavioral and motor disturbances. A substantiated inverse correlation between motor onset and the elongated CAG repeat in the HTT has been established. This relation does not account for the full variability of the motor onset, and efforts have been put into finding genetic modifiers of motor onset, however, mostly with unsuccessful outcome. In this study, we took an alternative approach focusing on symptom complexes and searched for modifiers of cognitive impairment and psychiatric symptoms in a well-described cohort of Danish HD gene-expansion carriers. We show that cognitive impairment and psychiatric symptoms in HD are modified by polymorphisms in the monoamine oxidase A (MAOA) and catechol-O-methyltransferase (COMT) genes and by the 4p16.3 B haplotype. These results support the theory of dopamine imbalance in HD, and point toward more personalized treatment modalities of HD in the future. PMID:26081309

  20. Androgen insensitivity syndrome: do trinucleotide repeats in androgen receptor gene have any role?

    Singh Rajender; Nalini J. Gupta; Baidyanath Chakravarty; Lalji Singh; Kumarasamy Thangaraj


    Aim: To investigate the role of CAG and GGN repeats as genetic background affecting androgen insensitivity syn- drome (AIS) phenotype. Methods: We analyzed lengths of androgen receptor (AR)-CAG and GGN repeats in 69 AIS cases, along with 136 unrelated normal male individuals. The lengths of repeats were analyzed using polymerase chain reaction (PCR) amplification followed by allelic genotyping to determine allele length. Results: Our study revealed significantly shorter mean lengths of CAG repeats in patients (mean 18.25 repeats, range 14-26 repeats) in comparison to the controls (mean 22.57 repeats, range 12-39 repeats) (two-tailed P < 0.0001). GGN repeats, however, did not differ significantly between patients (mean 21.48 repeats) and controls (mean 21.21 repeats) (two- tailed P = 0.474). Among patients' groups, the mean number of CAG repeats in partial androgen insensitivity cases (mean 15.83 repeats) was significantly less than in complete androgen insensitivity cases (mean 19.46 repeats) (two- tailed P < 0.0001). Conclusion: The findings suggest that shorter lengths of repeats in the AR gene might act as low penetrance genetic background in varying manifestation of androgen insensitivity. (Asian J Androl 2008 Jul; 10: 616-624)

  1. Distinct Diversity of the cag Pathogenicity Island among Helicobacter pylori Strains in Japan

    Azuma, Takeshi; Yamakawa, Akiyo; Yamazaki, Shiho; Ohtani, Masahiro; Ito, Yoshiyuki; Muramatsu, Atsushi; Suto, Hiroyuki; Yamazaki, Yukinao; Keida, Yoshihide; Higashi, Hideaki; Hatakeyama, Masanori


    The severity of Helicobacter pylori-related disease is correlated with the presence of a cag pathogenicity island (PAI). Genetic diversity within the cag PAI may have a modifying effect on the pathogenic potential of the infecting strain. We analyzed the complete cag PAI sequences of 11 representative Japanese strains according to their vacA genotypes and clinical effects and examined the relationship between the diversity of the cag PAI and clinical features. The cag PAI genes were divided i...

  2. Interactions between CagA and smoking in gastric cancer

    Xiao-Qin Wang; Hong Yan; Paul D Terry; Jian-Sheng Wang; Li Cheng; Wen-An Wu; Sen-Ke Hu


    AIM: To examine the interactions between cytotoxinassociated gene (CagA ) positive Helicobacter pylori infection and smoking in non-cardiac gastric cancer. METHODS: A case-control study (257 cases and 514 frequency-matched controls) was conducted from September 2008 to July 2010 in Xi'an, China. Cases were newly diagnosed, histologically confirmed non-cardiac cancer. Controls were randomly selected from similar communities to the cases and were further matched by sex and age (± 5 years). A face-to-face interview was performed by the investigators for each participant. Data were obtained using a standardized questionnaire that included questions regarding known or suspected lifestyle and environmental risk factors of gastric cancer. A 5 mL sample of fasting venous blood was taken. CagA infection was serologically detected by enzymelinked immunosorbent assays. RESULTS: Smoking and CagA infection were statistically significant risk factors of non-cardiac cancer. CagA was categorized in tertiles, and the odds ratio (OR) was 12.4 (95% CI: 6.1-20.3, P = 0.003) for CagA after being adjusted for confounding factors when the highexposure category was compared with the low-exposure category. Smokers had an OR of 5.4 compared with subjects who never smoked (95% CI: 2.3-9.0, P = 0.002). The OR of non-cardiac cancer was 3.5 (95% CI: 1.8-5.3) for non-smokers with CagA infection, 3.5 (95% CI: 1.9-5.1) for smokers without CagA infection, and 8.7 (95% CI: 5.1-11.9) for smokers with CagA infection compared with subjects without these risk factors. After adjusting for confounding factors, the corresponding ORs of non-cardiac cancer were 3.2 (95% CI: 1.5-6.8), 2.7 (95% CI: 1.3-4.9) and 19.5 (95% CI: 10.3-42.2), respectively. There was a multiplicative interaction between smoking and CagA , with a synergistic factor of 2.257 (Z = 2.315, P = 0.021). CONCLUSION: These findings support a meaningful interaction between CagA and smoking for the risk of gastric cancer which may have

  3. 5meCpG epigenetic marks neighboring a primate-conserved core promoter short tandem repeat indicate X-chromosome inactivation.

    Filipe Brum Machado

    Full Text Available X-chromosome inactivation (XCI is the epigenetic transcriptional silencing of an X-chromosome during the early stages of embryonic development in female eutherian mammals. XCI assures monoallelic expression in each cell and compensation for dosage-sensitive X-linked genes between females (XX and males (XY. DNA methylation at the carbon-5 position of the cytosine pyrimidine ring in the context of a CpG dinucleotide sequence (5meCpG in promoter regions is a key epigenetic marker for transcriptional gene silencing. Using computational analysis, we revealed an extragenic tandem GAAA repeat 230-bp from the landmark CpG island of the human X-linked retinitis pigmentosa 2 RP2 promoter whose 5meCpG status correlates with XCI. We used this RP2 onshore tandem GAAA repeat to develop an allele-specific 5meCpG-based PCR assay that is highly concordant with the human androgen receptor (AR exonic tandem CAG repeat-based standard HUMARA assay in discriminating active (Xa from inactive (Xi X-chromosomes. The RP2 onshore tandem GAAA repeat contains neutral features that are lacking in the AR disease-linked tandem CAG repeat, is highly polymorphic (heterozygosity rates approximately 0.8 and shows minimal variation in the Xa/Xi ratio. The combined informativeness of RP2/AR is approximately 0.97, and this assay excels at determining the 5meCpG status of alleles at the Xp (RP2 and Xq (AR chromosome arms in a single reaction. These findings are relevant and directly translatable to nonhuman primate models of XCI in which the AR CAG-repeat is monomorphic. We conducted the RP2 onshore tandem GAAA repeat assay in the naturally occurring chimeric New World monkey marmoset (Callitrichidae and found it to be informative. The RP2 onshore tandem GAAA repeat will facilitate studies on the variable phenotypic expression of dominant and recessive X-linked diseases, epigenetic changes in twins, the physiology of aging hematopoiesis, the pathogenesis of age-related hematopoietic

  4. Effects of Recent Stress and Variation in the Serotonin Transporter Polymorphism (5-HTTLPR) on Depressive Symptoms: A Repeated-Measures Study of Adults Age 50 and Older.

    Arpawong, Thalida E; Lee, Jinkook; Phillips, Drystan F; Crimmins, Eileen M; Levine, Morgan E; Prescott, Carol A


    Depending on genetic sensitivity to it, stress may affect depressive symptomatology differentially. Applying the stress-diathesis hypothesis to older adults, we postulate: (1) recent stress will associate with increased depressive symptom levels and (2) this effect will be greater for individuals with at least one short allele of the serotonin transporter gene promoter region (5-HTTLPR). Further, we employ a design that addresses specific limitations of many prior studies that have examined the 5-HTTLPR × SLE relation, by: (a) using a within-person repeated-measures design to address fluctuations that occur within individuals over time, increase power for detecting G × E, and address GE correlation; (b) studying reports of exogenous stressful events (those unlikely to be caused by depression) to help rule out reverse causation and negativity bias, and in order to assess stressors that are more etiologically relevant to depressive symptomatology in older adults. The sample is drawn from the Health and Retirement Study, a U.S. population-based study of older individuals (N = 28,248; mean age = 67.5; 57.3 % female; 80.7 % Non-Hispanic White, 14.9 % Hispanic/Latino, 4.5 % African American; genetic subsample = 12,332), from whom measures of depressive symptoms and exogenous stressors were collected biannually (1994-2010). Variation in the 5-HTTLPR was characterized via haplotype, using two single nucleotide polymorphisms (SNPs). Ordered logit models were constructed to predict levels of depressive symptoms from 5-HTTLPR and stressors, comparing results of the most commonly applied statistical approaches (i.e., comparing allelic and genotypic models, and continuous and categorical predictors) used in the literature. All models were stratified by race/ethnicity. Overall, results show a main effect of recent stress for all ethnic groups, and mixed results for the variation in 5-HTTLPR × stress interaction, contingent upon statistical model used. Findings

  5. Molecular analysis of the (CAGN repeat causing Huntington′s disease in 34 Iranian families

    Hormozian F


    Full Text Available Huntington′s disease (HD is an inherited neurodegenerative disorder characterized by chorea and progressive dementia. The mutation causing the disease has been identified as an unstable expansion of a trinucleotide (CAG n at the 5′ end of the IT 15 gene on chromosome 4. We have analyzed the distribution of CAG repeats in 71 Iranian individuals (34 patients and 37 unaffected family members belonging to 31 unrelated families thought to segregate HD. We found one expanded CAG allele in 22 individuals (65% belonging to 21 unrelated families. In these HD patients, expanded alleles varied from 40 to 83 CAG units and normal alleles varied from 13 to 36 CAGs. A significant negative correlation between age at onset of symptoms and size of the expanded CAG allele was found (r= - 0.51; P=0. 1. In addition, we genotyped 25 unrelated control individuals (total of 50 alleles and found normal CAG repeats varying from 10 to 34 units. In conclusion, our results showed that molecular confirmation of the clinical diagnosis in HD should be sought in all suspected patients, making it possible for adequate genetic counseling. This Study is the first report of molecular diagnosis of Huntington disease among Iranian population and ever in Middle East and with regard to high frequency of consanguinity marriage in this region.

  6. Construction of prokaryotic expression system of 2 148-bp fragment from cagA gene and detection of cagA gene, CagA protein in Helicobacter pyloriisolates and its antibody in sera of patients

    Jie Yan; Yuan Wang; Shi-He Shao; Ya-Fei Mao; Hua-Wen Li; Yi-Hui Luo


    AIM: To construct a prokaryotic expression system of a Helicobacter pylori ( H pylori) cagA gene fragment and establish enzyme-linked immunosorbent assays (ELISA) for detecting CagA and its antibody, so as to understand the manner in which the infection of CagA-expressing H pylori (CagA+ H pylori) isolates cause diseases.METHODS: H pylori strains in gastric biopsy specimens from 156 patients with positive results in rapid urease test were isolated. PCR was used to detect the frequency of cagA gene in the 109 H pylori isolates and to amplify a 2 148-bp fragment (cagA1) of cagA gene from a clinical strain Y06. A prokaryotic expression system of cagA1 gene was constructed,and the expression of the target recombinant protein (rCagA1) was examined by SDS-PAGE. Western blotting and immunodiffusion assay were employed to determine the immunoreactivity and antigenicity of rCagA1, respectively.Two ELISAs were established to detect CagA expression in 109 H pylori isolates and the presence of CagA antibody in the corresponding patients′ sera, and the correlations between infection with CagA+ H pylori and gastritis as well as peptic ulcer were analyzed.RESULTS: Of all the clinical specimens obtained, 80.8%(126/156) were found to have H pylori isolates and 97.2%of the isolates (106/109) were positive for caaA gene. In comparison with the reported data, the cloned cagA1fragment possessed 94.83% and 93.30% homologies with the nucleotide and putative amino acid sequences,respectively. The output of rCagA1 produced by the constructed recombinant prokaryotic expression system was approximately 30% of the total bacterial protein, rCagA1was able to bind to the commercial antibody against the whole-cells of H pylori and to induce the immunized rabbits to produce antibody with an immunodiffusion titer of 1:4. A proportion as high as 92.6% of the H pylori isolates (101/109)expressed CagA and 88.1% of the patients′ serum samples (96/109) were CagA antibody-positive. The percentage of

  7. Evidence of functional brain reorganization on the basis of blood flow changes in the CAG140 knock-in mouse model of Huntington's disease.

    Wang, Zhuo; Stefanko, Daniel P; Guo, Yumei; Toy, William A; Petzinger, Giselle M; Jakowec, Michael W; Holschneider, Daniel P


    Neuroimaging, especially functional brain mapping, may provide insights into the distributed involvement of multiple brain regions and loops in disorders classically associated with pathology of a localized region. One example is Huntington's disease (HD), typically classified as a basal ganglia disorder. Here, we report genotypic differences in cerebral perfusion mapping in an HD mouse model characterized by a gene knock-in (KI) of a human exon 1 CAG140 expansion repeat (CAG140 KI mice). Animals were examined at 6 months and compared with wild-type littermates. Regional cerebral blood flow (rCBF) was mapped in the awake, nonrestrained, male mouse at rest using [C]-iodoantipyrine autoradiography and analyzed in three-dimensionally reconstructed brains by statistical parametric mapping. Our results showed significant changes in rCBF between CAG140 KI and WT mice, such that CAG140 KI animals showed hypoperfusion of the basal ganglia motor circuit and hyperperfusion of cerebellar-thalamic and somatosensory regions. Significant hypoperfusion was also noted in CAG140 KI mice in the prelimbic and cingulate cortex (medial prefrontal area) and the hippocampus - areas associated with cognitive processing and mood. Changes in rCBF were apparent in the absence of motor deficits (rotarod test) or atrophy in the striatum (caudate-putamen) or hemispheric volume. Our results suggest a functional reorganization of whole-brain networks at a presymptomatic stage in the life of the CAG140 KI mouse. Functional brain mapping in animals may, in the future, serve as a translational biomarker for identifying sites of early synaptic change in the HD brain and for directing targeted preclinical molecular studies and clinical therapies. PMID:27082842

  8. Exosomes as nanocarriers for systemic delivery of the Helicobacter pylori virulence factor CagA

    Asako Shimoda; Koji Ueda; Shin Nishiumi; Naoko Murata-Kamiya; Sada-atsu Mukai; Shin-ichi Sawada; Takeshi Azuma; Masanori Hatakeyama; Kazunari Akiyoshi


    CagA, encoded by cytotoxin-associated gene A (cagA), is a major virulence factor of Helicobacter pylori, a gastric pathogen involved in the development of upper gastrointestinal diseases. Infection with cagA-positive H. pylori may also be associated with diseases outside the stomach, although the mechanisms through which H. pylori infection promotes extragastric diseases remain unknown. Here, we report that CagA is present in serum-derived extracellular vesicles, known as exosomes, in patient...

  9. Based Upon Repeat Pattern (BURP): an algorithm to characterize the long-term evolution of Staphylococcus aureus populations based on spa polymorphisms

    Sammeth Michael; Rothgänger Jörg; Berssenbrügge Christoph; Weniger Thomas; Mellmann Alexander; Stoye Jens; Harmsen Dag


    Abstract Background For typing of Staphylococcus aureus, DNA sequencing of the repeat region of the protein A (spa) gene is a well established discriminatory method for outbreak investigations. Recently, it was hypothesized that this region also reflects long-term epidemiology. However, no automated and objective algorithm existed to cluster different repeat regions. In this study, the Based Upon Repeat Pattern (BURP) implementation that is a heuristic variant of the newly described EDSI algo...

  10. Colorectal cancers in patients with the (9A/6A) polymorphism of TGFBR1 exhibit lesser inter-(simple sequence repeat) PCR genomic instability and present clinically at greater age.

    Dutt, Smitha S; Chen, Neng; Darbary, Huferesh K; Swede, Helen; Petrelli, Nicholas J; Stoler, Daniel L; Anderson, Garth R


    TGFbeta is involved in the response to DNA damage and signaling the cell cycle checkpoint response, in large part achieved by modulating the activity of the ATM kinase. We have investigated if the presence of a common polymorphism in the TGFbeta receptor TGFBR1 might impact genomic instability in human colorectal cancer. In order to obtain statistically significant numbers of patients with the lesser polymorphism, 177 colorectal cancer patients were genotyped for either the major form of the TGFBR1 receptor gene, homozygous for an internal segment of 9 alanines (9A/9A), or the lesser form, heterozygous for the polymorphism containing 6 alanines (9A/6A). Intrachromosomal genomic instability in the tumors was then quantified by the robust inter-(simple sequence repeat) PCR method. Tumors from all 26 patients heterozygous with the (9A/6A) polymorphism in TGFBR1 exhibited significantly lower genomic instability than from a randomly selected set [the first identified] of 37 patients with the (9A/9A) polymorphism (p=0.0002, Mann-Whitney). The median age of onset for the (9A/6A) patients was 70 years, compared with a median age of onset of 63 years for the patients carrying the (9A/9A) form (p=0.031, Mann-Whitney). These results are consistent with the model wherein genomic instability facilitates tumor progression, with lesser instability associated with later disease presentation. Clinically, our findings may be developed into improved screening guidelines with respect to the age at which colonoscopy is initiated in carriers of the TGFBR1*6A allele. PMID:18778720

  11. Translocation of Helicobacter pylori CagA into Gastric Epithelial Cells by Type IV Secretion

    Odenbreit, Stefan; Püls, Jürgen; Sedlmaier, Bettina; Gerland, Elke; Fischer, Wolfgang; Haas, Rainer


    The Gram-negative bacterium Helicobacter pylori is a causative agent of gastritis and peptic ulcer disease in humans. Strains producing the CagA antigen (cagA+) induce strong gastric inflammation and are strongly associated with gastric adenocarcinoma and MALT lymphoma. We show here that such strains translocate the bacterial protein CagA into gastric epithelial cells by a type IV secretion system, encoded by the cag pathogenicity island. CagA is tyrosine-phosphorylated and induces changes in the tyrosine phosphorylation state of distinct cellular proteins. Modulation of host cells by bacterial protein translocation adds a new dimension to the chronic Helicobacter infection with yet unknown consequences.

  12. Distinct Diversity of vacA, cagA, and cagE Genes of Helicobacter pylori Associated with Peptic Ulcer in Japan

    Yamazaki, Shiho; Yamakawa, Akiyo; Okuda, Tomoyuki; Ohtani, Masahiro; Suto, Hiroyuki; Ito, Yoshiyuki; Yamazaki, Yukinao; Keida, Yoshihide; Higashi, Hideaki; Hatakeyama, Masanori; Azuma, Takeshi


    Colonization of the stomach mucosa by Helicobacter pylori is a major cause of acute and chronic gastric pathologies in humans. Several H. pylori virulence genes that may play a role in its pathogenicity have been identified. The most important determinants are vacA and cagA in the cag pathogenicity island (cagPAI) genes. In the present study, to consider the association of molecular genetics between vacA and the cagPAI regarding clinical outcome, we selected H. pylori strains with various gen...

  13. Genome-Wide Analysis of Simple Sequence Repeats and Efficient Development of Polymorphic SSR Markers Based on Whole Genome Re-Sequencing of Multiple Isolates of the Wheat Stripe Rust Fungus.

    Huaiyong Luo

    Full Text Available The biotrophic parasitic fungus Puccinia striiformis f. sp. tritici (Pst causes stripe rust, a devastating disease of wheat, endangering global food security. Because the Pst population is highly dynamic, it is difficult to develop wheat cultivars with durable and highly effective resistance. Simple sequence repeats (SSRs are widely used as molecular markers in genetic studies to determine population structure in many organisms. However, only a small number of SSR markers have been developed for Pst. In this study, a total of 4,792 SSR loci were identified using the whole genome sequences of six isolates from different regions of the world, with a marker density of one SSR per 22.95 kb. The majority of the SSRs were di- and tri-nucleotide repeats. A database containing 1,113 SSR markers were established. Through in silico comparison, the previously reported SSR markers were found mainly in exons, whereas the SSR markers in the database were mostly in intergenic regions. Furthermore, 105 polymorphic SSR markers were confirmed in silico by their identical positions and nucleotide variations with INDELs identified among the six isolates. When 104 in silico polymorphic SSR markers were used to genotype 21 Pst isolates, 84 produced the target bands, and 82 of them were polymorphic and revealed the genetic relationships among the isolates. The results show that whole genome re-sequencing of multiple isolates provides an ideal resource for developing SSR markers, and the newly developed SSR markers are useful for genetic and population studies of the wheat stripe rust fungus.

  14. Evaluation of the Pattern of EPIYA Motifs in the Helicobacter pylori cagA Gene of Patients with Gastritis and Gastric Adenocarcinoma from the Brazilian Amazon Region.

    Vilar E Silva, Adenielson; Junior, Mario Ribeiro da Silva; Vinagre, Ruth Maria Dias Ferreira; Santos, Kemper Nunes; da Costa, Renata Aparecida Andrade; Fecury, Amanda Alves; Quaresma, Juarez Antônio Simões; Martins, Luisa Caricio


    The Helicobacter pylori is associated with the development of different diseases. The clinical outcome of infection may be associated with the cagA bacterial genotype. The aim of this study was to determine the EPIYA patterns of strains isolated from patients with gastritis and gastric adenocarcinoma and correlate these patterns with the histopathological features. Gastric biopsy samples were selected from 384 patients infected with H. pylori, including 194 with chronic gastritis and 190 with gastric adenocarcinoma. The presence of the cagA gene and the EPIYA motif was determined by PCR. The cagA gene was more prevalent in patients with gastric cancer and was associated with a higher degree of inflammation, neutrophil activity, and development of intestinal metaplasia. The number of EPIYA-C repeats showed a significant association with an increased risk of gastric carcinoma (OR = 3.79, 95% CI = 1.92-7.46, and P = 0.002). A larger number of EPIYA-C motifs were also associated with intestinal metaplasia. In the present study, infection with H. pylori strains harboring more than one EPIYA-C motif in the cagA gene was associated with the development of intestinal metaplasia and gastric adenocarcinoma but not with neutrophil activity or degree of inflammation. PMID:26904732

  15. A highly polymorphic (ACT)n VNTR (variable nucleotide of tandem repeats) locus inside intron 12 of COL1A2, one of the two genes involved in dominant osteogenesis imperfecta.

    Pepe, G


    A new, highly polymorphic, region consisting of variable number of tandem repeats (VNTR) is described that occurs within intron 12 of the COL1A2 gene. This VNTR consists of the trinucleotide ACT repeated from 6 to 12 times. Of the six alleles so far detected four are common in the three major races. The two rare alleles, (ACT)11 and (ACT)12, have been found only in Africans. In addition, a rapid technique has been developed that can be used successfully with very small amounts of even partially degraded DNA, thus allowing the use of this VNTR for forensic applications. Since dominant OI can be due to mutations at either of two loci (COL1A1 and COL1A2) prenatal diagnosis becomes feasible in the majority of the affected families only if a very informative marker is available for both of these genes. This VNTR provides a very powerful marker for COL1A2. In fact the heterozygosity for it ranges from 0.634 to 0.741 with PIC values from 0.562 to 0.696, respectively. Since trinucleotide repeats can be "unstable," and sometimes pathogenic, the unexplained collagenopathies (or suspected collagenopathies) should be analyzed from this point of view. PMID:8104634

  16. Distinct diversity of the cag pathogenicity island among Helicobacter pylori strains in Japan.

    Azuma, Takeshi; Yamakawa, Akiyo; Yamazaki, Shiho; Ohtani, Masahiro; Ito, Yoshiyuki; Muramatsu, Atsushi; Suto, Hiroyuki; Yamazaki, Yukinao; Keida, Yoshihide; Higashi, Hideaki; Hatakeyama, Masanori


    The severity of Helicobacter pylori-related disease is correlated with the presence of a cag pathogenicity island (PAI). Genetic diversity within the cag PAI may have a modifying effect on the pathogenic potential of the infecting strain. We analyzed the complete cag PAI sequences of 11 representative Japanese strains according to their vacA genotypes and clinical effects and examined the relationship between the diversity of the cag PAI and clinical features. The cag PAI genes were divided into two major groups, a Western and a Japanese group, by phylogenetic analysis based on the entire cag PAI sequences. The predominant Japanese strains formed a Japanese cluster which was different from the cluster formed by Western strains. The diversity of the cag PAI was associated with the vacA and cagA genotypes. All strains with the s1c vacA genotype were in the Japanese cluster. In addition, all strains with the East Asian-type cagA genotype were also in the Japanese cluster. Patients infected with the Japanese-cluster strain had high-grade gastric mucosal atrophy. These results suggest that a distinct diversity of the cag PAI of H. pylori is present among Japanese strains and that this diversity may be involved in the development of atrophic gastritis and may increase the risk for gastric cancer. PMID:15184428

  17. Distinct diversity of vacA, cagA, and cagE genes of Helicobacter pylori associated with peptic ulcer in Japan.

    Yamazaki, Shiho; Yamakawa, Akiyo; Okuda, Tomoyuki; Ohtani, Masahiro; Suto, Hiroyuki; Ito, Yoshiyuki; Yamazaki, Yukinao; Keida, Yoshihide; Higashi, Hideaki; Hatakeyama, Masanori; Azuma, Takeshi


    Colonization of the stomach mucosa by Helicobacter pylori is a major cause of acute and chronic gastric pathologies in humans. Several H. pylori virulence genes that may play a role in its pathogenicity have been identified. The most important determinants are vacA and cagA in the cag pathogenicity island (cagPAI) genes. In the present study, to consider the association of molecular genetics between vacA and the cagPAI regarding clinical outcome, we selected H. pylori strains with various genotypes of vacA in Japan and sequenced full-length vacA, cagA, and cagE genes. Sequencing of vacA and cagA genes revealed variable size, whereas the cagE gene was well conserved among strains. Each of the phylogenetic trees based on the deduced amino acid sequences of VacA, CagA, and CagE indicated that all three proteins were divided into two major groups, a Western group and an East Asian group, and the distributions of isolates exhibited similar patterns among the three proteins. The strains with s2 and s1a/m1a vacA genotypes and the Western-type 3' region cagA genotype were classified into the Western group, and the strains with the s1c/m1b vacA genotype and the East Asian-type 3' cagA genotype were included in the East Asian group. In addition, the prevalence of infection with the Western group strain was significantly higher in patients with peptic ulcer (90.0%, 9/10) than in patients with chronic gastritis (22.7%, 5/22) (chi2 = 12.64, P = 0.00057). These data suggest that the molecular genetics of vacA and cagPAI are associated and that the Western group with vacA and cagPAI genes is associated with peptic ulcer disease. PMID:16081930

  18. Based Upon Repeat Pattern (BURP: an algorithm to characterize the long-term evolution of Staphylococcus aureus populations based on spa polymorphisms

    Sammeth Michael


    Full Text Available Abstract Background For typing of Staphylococcus aureus, DNA sequencing of the repeat region of the protein A (spa gene is a well established discriminatory method for outbreak investigations. Recently, it was hypothesized that this region also reflects long-term epidemiology. However, no automated and objective algorithm existed to cluster different repeat regions. In this study, the Based Upon Repeat Pattern (BURP implementation that is a heuristic variant of the newly described EDSI algorithm was investigated to infer the clonal relatedness of different spa types. For calibration of BURP parameters, 400 representative S. aureus strains with different spa types were characterized by MLST and clustered using eBURST as "gold standard" for their phylogeny. Typing concordance analysis between eBURST and BURP clustering (spa-CC were performed using all possible BURP parameters to determine their optimal combination. BURP was subsequently evaluated with a strain collection reflecting the breadth of diversity of S. aureus (JCM 2002; 40:4544. Results In total, the 400 strains exhibited 122 different MLST types. eBURST grouped them into 23 clonal complexes (CC; 354 isolates and 33 singletons (46 isolates. BURP clustering of spa types using all possible parameter combinations and subsequent comparison with eBURST CCs resulted in concordances ranging from 8.2 to 96.2%. However, 96.2% concordance was reached only if spa types shorter than 8 repeats were excluded, which resulted in 37% excluded spa types. Therefore, the optimal combination of the BURP parameters was "exclude spa types shorter than 5 repeats" and "cluster spa types into spa-CC if cost distances are less than 4" exhibiting 95.3% concordance to eBURST. This algorithm identified 24 spa-CCs, 40 singletons, and excluded only 7.8% spa types. Analyzing the natural population with these parameters, the comparison of whole-genome micro-array groupings (at the level of 0.31 Pearson correlation index

  19. Neutral Polymorphisms in Putative Housekeeping Genes and Tandem Repeats Unravels the Population Genetics and Evolutionary History of Plasmodium vivax in India

    Prajapati, Surendra K.; Joshi, Hema; Carlton, Jane M.; Rizvi, M. Alam


    The evolutionary history and age of Plasmodium vivax has been inferred as both recent and ancient by several studies, mainly using mitochondrial genome diversity. Here we address the age of P. vivax on the Indian subcontinent using selectively neutral housekeeping genes and tandem repeat loci. Analysis of ten housekeeping genes revealed a substantial number of SNPs (n = 75) from 100 P. vivax isolates collected from five geographical regions of India. Neutrality tests showed a majority of the ...

  20. DNA repair gene polymorphisms and risk of chronic atrophic gastritis: a case-control study

    Raum Elke


    Full Text Available Abstract Background Recent studies have reported associations of DNA repair pathway gene variants and risk of various cancers and precancerous lesions, such as chronic atrophic gastritis (CAG. Methods A nested case-control study within the German population-based ESTHER cohort was conducted, including 533 CAG cases and 1054 controls. Polymorphisms in eleven DNA repair genes (APEX1, ERCC1, ERCC2/XPD, PARP1 and XRCC1, in CD3EAP/ASE-1 and PPP1R13L were analysed. Results No association was disclosed for any of the analysed polymorphisms. Nor did stratified analyses according to ages Conclusions The results of this large German case-control study do not reveal associations of DNA repair pathway polymorphisms and risk of CAG. On the basis of a large number of CAG cases, they do not support associations of DNA repair pathway SNPs with CAG risk, but suggest the need of larger studies to disclose or exclude potential weak associations, or of studies with full coverage of candidate genes.

  1. Helicobacter pylori CagA Inhibits PAR1-MARK Family Kinases by Mimicking Host Substrates

    Nesic, D.; Miller, M; Quinkert, Z; Stein, M; Chait, B; Stebbins, C


    The CagA protein of Helicobacter pylori interacts with numerous cellular factors and is associated with increased virulence and risk of gastric carcinoma. We present here the cocrystal structure of a subdomain of CagA with the human kinase PAR1b/MARK2, revealing that a CagA peptide mimics substrates of this kinase family, resembling eukaryotic protein kinase inhibitors. Mutagenesis of conserved residues central to this interaction renders CagA inactive as an inhibitor of MARK2.

  2. An RGD helper sequence in CagL of Helicobacter pylori assists in interactions with integrins and injection of CagA

    Jens eConradi


    Full Text Available Helicobacter pylori is a specific gastric pathogen that colonizes the stomach in more than 50% of the world’s human population. Infection with this bacterium can induce several types of gastric pathology, ranging from chronic gastritis to peptic ulcers and even adenocarcinoma. Virulent H. pylori isolates encode components of a type IV secretion system (T4SS, which form a pilus for the injection of virulence proteins such as CagA into host target cells. This is accomplished by a specialized adhesin on the pilus surface, the protein CagL, a putative VirB5 ortholog, which binds to host cell β1 integrin, triggering subsequent delivery of CagA across the host cell membrane. Like the human extracellular matrix protein fibronectin, CagL contains an RGD (Arg-Gly-Asp motif and is able to trigger intracellular signaling pathways by RGD-dependent binding to integrins. While CagL binding to host cells is mediated primarily by the RGD motif, we identified an auxiliary binding motif for CagL-integrin interaction. Here, we report on a surface-exposed FEANE (Phe-Glu-Ala-Asn-Glu interaction motif in spatial proximity to the RGD sequence, which enhances the interactions of CagL with integrins. It will be referred to as RGD helper sequence (RHS. Competitive cell adhesion assays with recombinant wild type CagL and point mutants, competition experiments with synthetic cyclic and linear peptides, and peptide array experiments revealed amino acids essential for the interaction of the RHS motif with integrins. Infection experiments indicate that the RHS motif plays a role in the early interaction of H. pylori T4SS with integrin, to trigger signaling and to inject CagA into host cells. We thus postulate that CagL is a versatile T4SS surface protein equipped with at least two motifs to promote binding to integrins, thereby causing aberrant signaling within host cells and facilitating translocation of CagA into host cells, thus contributing directly to H. pylori

  3. Study of the cytoxin-associated gene a (CagA gene in Helicobacter pylori using gastric biopsies of Iraqi patients

    Elham A Kalaf


    Full Text Available Background and Aims: The Helicobacter pylori CagA gene is a major virulence factor that plays an important role in gastric pathologies. The size variation of CagA gene, which is dependent on the 3′ repeat region, contains one or more Glu-Pro-Ile-Tyr-Ala (EPIYA motifs and CagA multimerization (CM motifs. Four segments flanking the EPIYA motifs, EPIYA −A, −B, −C, or −D, were reported to play a crucial role in the pathogenesis of H. pylori infection. The aim was to determine the roles of EPIYA segments and CM motifs in gastroduodenal pathogenesis in an Iraqi population. Patients and Methods: Gastric biopsies were collected from 210 patients with gastritis, duodenal ulcer (DU, gastric ulcer (GU, and gastric cancer (GC. The EPIYA motif genotyping was determined by polymerase chain reaction and sequencing. The differences in age, gender, and CagA EPIYA motifs of H. pylori between GC, DU, GU and gastritis patients were analyzed using a χ 2 -test. Results : A total of 22 (45.8% strains had three copies of EPIYA (ABC type, 2 (4.16% had four copies (ABCC type, 6 (12.7% had five copies (ABCCC type, 13 (27.08% had two copies (AB type, 3 (6.25% had the BC, and 2 (4.17% had AC motif. The alignment of the deduced protein sequences confirmed that there were no East Asian type EPIYA-D sequences in Iraqi strains. A significant association was found between increase in number of EPIYA-C motifs and GU (P ≤ 0.01 compared with gastritis. Conclusions: The structure of the 3′ region of the CagA gene in Iraqi strains was Western type with a variable number of EPIYA-C and CM motifs. A significant association was found between increase in number of EPIYA-C motifs and GU compared with gastritis indicating predictive association with the severity of the disease. The GenBank accession numbers for the partial CagA nucleotide sequences determined in this study are JX164093-JX164112.

  4. Repeated Miscarriage

    f AQ FREQUENTLY ASKED QUESTIONS FAQ100 PREGNANCY Repeated Miscarriages • What is recurrent pregnancy loss? • What is the likelihood of having repeated miscarriages? • What is the most common cause of miscarriage? • ...

  5. Cloning and sequencing of cagA gene fragment of Helicobacter pylori with coccoid form

    Ke-Xia Wang; Xue-Feng Wang


    AIM: To clone and sequence the cagA gene fragment of Helicobacter pylori ( H pylori) with coccoid form.METHODS: H pylori strain NCTC11637 were transformed to coccoid form by exposure to antibiotics in subinhibitory concentrations. The coccoid H pyloriwas collected. cagA gene of the coccoid H pylori strain was amplified by PCR.After purified, the target fragment was cloned into plasmid pMD-18T. The recombinant plasmid pMD-18T-cagA was transformed into E. coli JM109. Positive clones were screened and identified by PCR and digestion with restriction endonucleases. The sequence of inserted fragment was then analysed.RESULTS: cagA gene of 3 444 bp was obtained from the coccoid H pylori genome DNA. The recombinant plasmid pMD-18T-cagA was constructed, then it was digested by BamH Ⅰ+Sac Ⅰ, and the product of digestion was identical with the predicted one. Sequence analysis showed that the homology of coccoid and the reported original sequence H pylori was 99.7%.CONCLUSION: The recombinant plasmid containing cagA gene from coccoid H pylori has been constructed successfully.The coccoid H pylori contain completed cagA gene, which may be related to pathogenicity of them.

  6. Determination of genotypic diversity of Mycobacterium avium subspecies from human and animal origins by mycobacterial interspersed repetitive-unit-variable-number tandem-repeat and IS1311 restriction fragment length polymorphism typing methods.

    Radomski, Nicolas; Thibault, Virginie C; Karoui, Claudine; de Cruz, Krystel; Cochard, Thierry; Gutiérrez, Cristina; Supply, Philip; Biet, Frank; Boschiroli, María Laura


    Members of the Mycobacterium avium complex (MAC) are ubiquitous bacteria that can be found in water, food, and other environmental samples and are considered opportunistic pathogens for numerous animal species, mainly birds and pigs, as well as for humans. We have recently demonstrated the usefulness of a PCR-based mycobacterial interspersed repetitive-unit-variable-number tandem-repeat (MIRU-VNTR) typing for the molecular characterization of M. avium subsp. paratuberculosis and M. avium strains exclusively isolated from AIDS patients. In the present study we extended our analysis, based on eight MIRU-VNTR markers, to a strain collection comprehensively comprising the other M. avium subspecies, including M. avium subsp. avium, M. avium subsp. hominissuis, and M. avium subsp. silvaticum, isolated from numerous animal species, HIV-positive and HIV-negative humans, and environmental sources. All strains were fully typeable, with the discriminatory index being 0.885, which is almost equal to that obtained by IS1311 restriction fragment length polymorphism (RFLP) typing as a reference. In contrast to IS1311 RFLP typing, MIRU-VNTR typing was able to further discriminate M. avium subsp. avium strains. MIRU-VNTR alleles strongly associated with or specific for M. avium subspecies were detected in several markers. Moreover, the MIRU-VNTR typing-based results were consistent with a scenario of the independent evolution of M. avium subsp. avium/M. avium subsp. silvaticum and M. avium subsp. paratuberculosis from M. avium subsp. hominissuis, previously proposed on the basis of multilocus sequence analysis. MIRU-VNTR typing therefore appears to be a convenient typing method capable of distinguishing the three main subspecies and strains of the complex and providing new epidemiological knowledge on MAC. PMID:20107094

  7. Diagnostic value of CagA IgG in the process to eradicate Helicobacter pylori

    Zhi Bang Yang; Pi Long Wang; Ming Ming Gu; Li Hao Chen; Quan Chen; Lin Zhan


    AIM To investigate the diagnostic value of CagA IgG in serum.METHODS Seventy three patients with peptic ulcer infected with HP were eradicated by antibioticstherapy. At pretreatment, wk9 and wk20 after treatment, the detection of Hp in gastric muscosa bybacteriologic method were performed, and CagA and whole-cell antigen of HP igG in serum by ELISAmethod were also performed at the same time.RESULTS The IgG titres of Hp CagA and whole-cell antigen changes in accordance with the efficacy ofHp eradicated. The former with an earlier appearance and a greater number of cases decreased to normallevel in comparison with the latter.CONCLUSION CagA IgG is a better index for observing the effectiveness of the eradication of Hp.

  8. Prevalence of Helicobacter pylori cagA genotype among dyspeptic patients in Southern Thailand

    Sueptrakool Wisessombat; Chatruthai Meethai


    Objective: To investigate the prevalence of Helicobacter pylori (H. pylori) infection in dyspepsia patients and its relation to virulence factor cagA gene. Methods: In total, 110 gastric biopsies from dyspeptic patients were comparatively studied using rapid urease test and multiplex polymerase chain reaction (PCR). Results: Multiplex PCR detected three genes of 16S rRNA, cagA, and ureC. H. pylori was detected in 14 gastric biopsies (13%). Significantly higher numbers of female were infected. Furthermore,cag A gene was found in all H. pylori-positive specimens. In addition, the result indicated that the multiplex PCR with annealing temperature at 57 oC was able to effectively amplify specific products. Conclusions:The results confirmed high prevalence of cagA gene in H. pylori among dyspeptic patients in Southern Thailand.

  9. Molecular mechanisms of gastric epithelial cell adhesion and injection of CagA by Helicobacter pylori

    Backert Steffen


    Full Text Available Abstract Helicobacter pylori is a highly successful pathogen uniquely adapted to colonize humans. Gastric infections with this bacterium can induce pathology ranging from chronic gastritis and peptic ulcers to gastric cancer. More virulent H. pylori isolates harbour numerous well-known adhesins (BabA/B, SabA, AlpA/B, OipA and HopZ and the cag (cytotoxin-associated genes pathogenicity island encoding a type IV secretion system (T4SS. The adhesins establish tight bacterial contact with host target cells and the T4SS represents a needle-like pilus device for the delivery of effector proteins into host target cells such as CagA. BabA and SabA bind to blood group antigen and sialylated proteins respectively, and a series of T4SS components including CagI, CagL, CagY and CagA have been shown to target the integrin β1 receptor followed by injection of CagA across the host cell membrane. The interaction of CagA with membrane-anchored phosphatidylserine may also play a role in the delivery process. While substantial progress has been made in our current understanding of many of the above factors, the host cell receptors for OipA, HopZ and AlpA/B during infection are still unknown. Here we review the recent progress in characterizing the interactions of the various adhesins and structural T4SS proteins with host cell factors. The contribution of these interactions to H. pylori colonization and pathogenesis is discussed.

  10. Association of cyclooxygenase-2 expression with Hp-cagA infection in gastric cancer

    Xiao-Lin Guo; Li-Er Wang; Shu-Yan Du; Chen-Ling Fan; Li Li; Peng Wang; Yuan Yuan


    AIM: To observe the expression of cyclooxygenase-2 (COX-2) and to investigate the association between COX-2expression and infection with cytotoxic-associated gene A( cagA) positive strair Helicobacter pylori ( Hp) in humangastric cancer, and subsequently to provide fresh ideas forthe early prevention of gastric cancer.METHODS: 32 Specimens of gastric cancer andcorresponding adjacent normal gastric mucosa were obtainedfrom patients who had undergone surgical operations ofgastric cancer. All the samples including 1 case of stomachmalignant lymphoma and 31 cases of gastric adenocarcinomawere confirmed by pathology diagnosis. The expression ofCOX-2 in 32 specimens of gastric cancer and correspondingadjacent normal gastric mucosa was quantitativelydetermined and analyzed with Flow Cytometry, and the levelsof COX-2 protein were compared between specimens withcagA+ Hp infection and those without cagA+ Hp infection.The cagA gene in 32 specimens of gastric cancer wasdetected bypolymerase chain reaction (PCR) method.RESULTS: Twenty-seven of 32 (84 %) specimens of gastriccancer showed over-expression of COX-2, compared withthe adjacent normal gastric mucosa. cagA+ gene weredetected from 19 specimens of gastric cancer, but not fromthe other 13 specimens. The levels of COX-2 protein in 19specimens of gastric cancer with cagA+ Hp infection (thenumber of positive cells was 73.82±18.2) were significantlyhigher than those in the 13 specimens without cagA+ Hpinfection (the number of positive cells was 35.92±22.1).CONCLUSION: COX-2 is overexpressed in gastric cancerand cagA+Hp infection could up-regulate the expression ofCOX-2 in gastric cancer in human. There may also existanother way or channel to regulate the expression of COX-2 in gastric cancer in addition to cagA+Hp infection.Therefore, applying COX-2 selective inhibitors could be aneffective and promising way to prevent gastric cancer.

  11. Molecular mechanisms of gastric epithelial cell adhesion and injection of CagA by Helicobacter pylori

    Backert, Steffen


    Abstract Helicobacter pylori is a highly successful pathogen uniquely adapted to colonize humans. Gastric infections with this bacterium can induce pathology ranging from chronic gastritis and peptic ulcers to gastric cancer. More virulent H. pylori isolates harbour numerous well-known adhesins (BabA\\/B, SabA, AlpA\\/B, OipA and HopZ) and the cag (cytotoxin-associated genes) pathogenicity island encoding a type IV secretion system (T4SS). The adhesins establish tight bacterial contact with host target cells and the T4SS represents a needle-like pilus device for the delivery of effector proteins into host target cells such as CagA. BabA and SabA bind to blood group antigen and sialylated proteins respectively, and a series of T4SS components including CagI, CagL, CagY and CagA have been shown to target the integrin β1 receptor followed by injection of CagA across the host cell membrane. The interaction of CagA with membrane-anchored phosphatidylserine may also play a role in the delivery process. While substantial progress has been made in our current understanding of many of the above factors, the host cell receptors for OipA, HopZ and AlpA\\/B during infection are still unknown. Here we review the recent progress in characterizing the interactions of the various adhesins and structural T4SS proteins with host cell factors. The contribution of these interactions to H. pylori colonization and pathogenesis is discussed.

  12. Repeat associated non-ATG translation initiation: one DNA, two transcripts, seven reading frames, potentially nine toxic entities!

    Christopher E Pearson


    Full Text Available Diseases associated with unstable repetitive elements in the DNA, RNA, and amino acids have consistently revealed scientific surprises. Most diseases are caused by expansions of trinucleotide repeats, which ultimately lead to diseases like Huntington's disease, myotonic dystrophy, fragile X syndrome, and a series of spinocerebellar ataxias. These repeat mutations are dynamic, changing through generations and within an individual, and the repeats can be bi-directionally transcribed. Unsuspected modes of pathogenesis involve aberrant loss of protein expression; aberrant over-expression of non-mutant proteins; toxic-gain-of-protein function through expanded polyglutamine tracts that are encoded by expanded CAG tracts; and RNA-toxic-gain-of-function caused by transcripts harboring expanded CUG, CAG, or CGG tracts. A recent advance reveals that RNA transcripts with expanded CAG repeats can be translated in the complete absence of a starting ATG, and this Repeat Associated Non-ATG translation (RAN-translation occurs across expanded CAG repeats in all reading frames (CAG, AGC, and GCA to produce homopolymeric proteins of long polyglutamine, polyserine, and polyalanine tracts. Expanded CTG tracts expressing CUG transcripts also show RAN-translation occurring in all three frames (CUG, UGC, and GCU, to produce polyleucine, polycysteine, and polyalanine. These RAN-translation products can be toxic. Thus, one unstable (CAG•(CTG DNA can produce two expanded repeat transcripts and homopolymeric proteins with reading frames (the AUG-directed polyGln and six RAN-translation proteins, yielding a total of potentially nine toxic entities. The occurrence of RAN-translation in patient tissues expands our horizons of modes of disease pathogenesis. Moreover, since RAN-translation counters the canonical requirements of translation initiation, many new questions are now posed that must be addressed. This review covers RAN-translation and some of the pertinent

  13. Polymorphism in the Helicobacter pylori CagA and VacA toxins and disease

    Bridge, Dacie R.; Merrell, D. Scott


    Half of the world’s population is infected with Helicobacter pylori and approximately 20% of infected individuals develop overt clinical disease such as ulcers and stomach cancer. Paradoxically, despite its classification as a class I carcinogen, H. pylori has been shown to be protective against development of asthma, allergy, and esophageal disease. Given these conflicting roles for H. pylori, researchers are attempting to define the environmental, host, and pathogen interactions that ultima...

  14. ProtRepeatsDB: a database of amino acid repeats in genomes

    Chauhan Virander S


    Full Text Available Abstract Background Genome wide and cross species comparisons of amino acid repeats is an intriguing problem in biology mainly due to the highly polymorphic nature and diverse functions of amino acid repeats. Innate protein repeats constitute vital functional and structural regions in proteins. Repeats are of great consequence in evolution of proteins, as evident from analysis of repeats in different organisms. In the post genomic era, availability of protein sequences encoded in different genomes provides a unique opportunity to perform large scale comparative studies of amino acid repeats. ProtRepeatsDB is a relational database of perfect and mismatch repeats, access to which is designed as a resource and collection of tools for detection and cross species comparisons of different types of amino acid repeats. Description ProtRepeatsDB (v1.2 consists of perfect as well as mismatch amino acid repeats in the protein sequences of 141 organisms, the genomes of which are now available. The web interface of ProtRepeatsDB consists of different tools to perform repeat s; based on protein IDs, organism name, repeat sequences, and keywords as in FASTA headers, size, frequency, gene ontology (GO annotation IDs and regular expressions (REGEXP describing repeats. These tools also allow formulation of a variety of simple, complex and logical queries to facilitate mining and large-scale cross-species comparisons of amino acid repeats. In addition to this, the database also contains sequence analysis tools to determine repeats in user input sequences. Conclusion ProtRepeatsDB is a multi-organism database of different types of amino acid repeats present in proteins. It integrates useful tools to perform genome wide queries for rapid screening and identification of amino acid repeats and facilitates comparative and evolutionary studies of the repeats. The database is useful for identification of species or organism specific

  15. Intergeneration CAG expansion in a Wuhan juvenile-onset Huntingto ndisease family%武汉地区CAG扩增突变致青少年发病的亨廷顿舞蹈病的家系分析

    刘媛; 沈滟; 李和; 王慧; 杨真荣; 陈燕; 唐艳平


    目的 对青少年发病的亨廷顿舞蹈病(Huntington disease)家系进行致病IT15基因早期诊断分析,为家系成员提供遗传咨询,并为后续的HD发病机制及实验治疗研究提供依据.方法 按照知情同意原则抽取家系成员外周血,提取基因组DNA,采用改良的降落PCR方法扩增IT15基因致病区域,DNA测序检测异常等位基因(CAG)n三核苷酸重复次数.结果 在该家系三代25名成员中,共发现8名致病IT15基因携带者,其中,Ⅲ10、Ⅲ12、Ⅲ14、Ⅳ3和Ⅴ2 CAG三核苷酸的拷贝数均为48,Ⅳ11和Ⅳ12均为(CAG)67,Ⅳ14为(CAG)63,而对照组35名正常人的CAG三核苷酸的拷贝数为8-25,两者之间没有重叠.结论 家系中第四代致病基因携带者Ⅳ14与第三代患者Ⅲ10比较,CAG三核苷酸重复次数增加15次,即本家系IT15基因在传递过程中发生了扩增突变.同时,扩增突变导致该家系出现青少年发病及遗传早现现象.%Objective To make early diagnosis of IT15 gene mutation in a Wuhan juvenile-onset Huntington disease (HD)family, for providing them with genetic counseling, and making preparation for the further research on pathogenesis and experimental therapy of HD. Methods According to the principle of informed consent, we extracted genomic DNA from peripheral blood samples and carried genetic diagnosis of pathogenic exon 1 of IT15 gene by modified touchdown PCR and DNA sequencing methods. Results Eight of twenty-five family members carried abnormal allele: Ⅲ10, Ⅲ12, Ⅲ14, Ⅳ3,and Ⅴ2 carried (CAG) 48, Ⅳ11 and Ⅳ12 carried (CAG) 67, and Ⅳ14 carried (CAG) 63, in contrast with the 8-25 CAG trinucleotides in the members of control group. Ⅳ14 carried 15 more CAG trinucleotides than her father Ⅲ10. Conclusion The results definitely confirm the diagnosis of HD and indicate the CAG trinucleotide repeat expansion of IT15 gene in this HD family.In addition, CAG expansion results in juvenile-onset and anticipation (characterized

  16. Helicobacter pylori cagA and vacA genotypes in Cuban and Venezuelan populations

    Diana Ortiz-Princz


    Full Text Available The aim of this study was to determine the presence of Helicobacter pylori cytotoxin-associated gene (cagA/vacuolating cytotoxin gene (vacA among patients with chronic gastritis in Cuba and Venezuela. Gastric antrum biopsies were taken for culture, DNA extraction and PCR analysis. Amplification of vacA and cagA segments was performed using two regions of cagA: 349 bp were amplified with the F1/B1 primers and the remaining 335 bp were amplified with the B7629/B7628 primers. The VA1-F/VA1-R set of primers was used to amplify the 259-bp (s1 or 286-bp (s2 product and the VAG-R/VAG-F set of primers was used to amplify the 567-bp (m1 or 642-bp (m2 regions of vacA. cagA was detected in 87% of the antral samples from Cuban patients and 80.3% of those from Venezuelan patients. All possible combinations of vacA regions were found, with the exception of s2/m1. The predominant combination found in both countries was s1/m1. The percentage of cagA+ strains was increased by the use of a second set of primers and a greater number of strains was amplified with the B7629/B7628 primers in the Cuban patients (p = 0.0001. There was no significant difference between the presence of the allelic variants of vacA and cagA in both populations. The predominant genotype was cagA+/s1m1 in both countries. The results support the necessary investigation of isolates circulating among the human population in each region.

  17. cagE as a biomarker of the pathogenicity of Helicobacter pylori

    Ivy Bastos Ramis


    Full Text Available Introduction Helicobacter pylori infection is associated with gastro-duodenal diseases. Genes related to pathogenicity have been described for H. pylori and some of them appear to be associated with more severe clinical outcomes of the infection. The present study investigates the role of cagE as a pathogenicity biomarker of H. pylori compare it to cagA, vacA, iceA and babA2 genes and correlate with endoscopic diagnoses. Methods Were collected biopsy samples of 144 dyspeptic patients at the Hospital of the Federal University of Rio Grande, Rio Grande do Sul, Brazil. After collection, the samples were sent for histological examination, DNA extraction and detection of all putative pathogenicity genes by PCR. Results Of the 144 patients undergoing endoscopy, 57 (39.6% presented H. pylori by histological examination and PCR by detection of the ureA gene. Based on the endoscopic diagnoses, 45.6% (26/57 of the patients had erosive gastritis, while 54.4% (31/57 had enanthematous gastritis. The genes cagA, cagE, vacAs1/m1, vacAs1/m2 and iceA1 were related to erosive gastritis, while the genes vacAs2/m2, iceA2 and babA2 were associated to enanthematous gastritis. We found a statistically significant association between the presence of cagE and the endoscopic diagnosis. However, we detect no statistically significant association between the endoscopic diagnosis and the presence of cagA, vacA, iceA and babA2, although a biological association has been suggested. Conclusions Thus, cagE could be a risk biomarker for gastric lesions and may contribute to a better evaluation of the H. pylori pathogenic potential and to the prognosis of infection evolution in the gastric mucosa.

  18. Spinocerebellar ataxia type 2 (SCA2) in an Egyptian family presenting with polyphagia and marked CAG expansion in infancy.

    Abdel-Aleem, Alice; Zaki, Maha S


    We describe an Egyptian family having SCA2 affecting three generations with marked molecular and clinical anticipation observed in the index case. Our proband was a male child starting as early as 2 years old with progressive extrapyramidal manifestations, slow eye movements and cognitive impairment. A history of nonspecific mild developmental delay was recorded. The patient lost all cognitive functions, had persistent dystonic posture, trophic changes, vasomotor instability, dysphagia and died at the age of 7 years. The age at presentation among other affected family members varied between 11 and 45 years old across three generations. The early common neurological symptoms were choreoathetotic movements, myoclonic jerk, gait difficulty, expressionless face and emotional liability. Later, overt ataxia, incoordination, dysarthria, mild dementia and slow eye saccades predominated. Brisk tendon reflexes were detected in three cases. Peripheral nerve affection was a late manifestation. Interestingly, polyphagia and obesity were striking manifestations in the middle stage of the disease; an observation that might support a previously suggested relation between the ataxin-2 gene and body weight. The proband showed an amplified allele with marked CAG expansion in the form of a smear sized 69-75 repeats resulted from maternal transmission. To our knowledge, our index case is the second report in the literature presenting with infantile onset SCA2 and intermediate repeat expansion. This family expands the phenotypic spectrum of early onset SCA2 and points out the importance of considering SCA2 gene analysis in children with progressive neurological impairment and abnormal movements with or without polyphagia. PMID:18297329

  19. A Semiparametric Bayesian Model for Repeatedly Repeated Binary Outcomes

    Quintana, Fernando A.; Müller, Peter; Rosner, Gary L.; Mary V Relling


    We discuss the analysis of data from single nucleotide polymorphism (SNP) arrays comparing tumor and normal tissues. The data consist of sequences of indicators for loss of heterozygosity (LOH) and involve three nested levels of repetition: chromosomes for a given patient, regions within chromosomes, and SNPs nested within regions. We propose to analyze these data using a semiparametric model for multi-level repeated binary data. At the top level of the hierarchy we assume a sampling model fo...

  20. Synthesis and characterization of Fe 3 O 4 @C@Ag nanocomposites and their antibacterial performance

    Xia, Haiqing; Cui, Bin; Zhou, Junhong; Zhang, Lulu; Zhang, Ji; Guo, Xiaohui; Guo, Huilin


    We synthesized Fe 3O 4@C@Ag nanocomposites through a combination of solvothermal, hydrothermal, and chemical redox reactions. Characterization of the resulting samples by X-ray diffraction, Fourier-transform infrared spectroscopy, field-emission scanning and transmission electron microscopy, and magnetic measurement is reported. Compared to Fe 3O 4@Ag nanocomposites, the Fe 3O 4@C@Ag nanocomposites showed enhanced antibacterial activity. The Fe 3O 4@C@Ag nanocomposites were able to almost entirely prevent growth of Escherichia coli when the concentration of Ag nanoparticles was 10 μg/mL. Antibacterial activity of the Fe 3O 4@C@Ag nanocomposites was maintained for more than 40 h at 37 °C. The intermediate carbon layer not only protects magnetic core, but also improves the dispersion and antibacterial activity of the silver nanoparticles. The magnetic core can be used to control the specific location of the antibacterial agent (via external magnetic field) and to recycle the residual silver nanoparticles. The Fe 3O 4@C@Ag nanocomposites will have potential uses in many fields as catalysts, absorbents, and bifunctional magnetic-optical materials.

  1. ABO blood groups and Helicobacter pylori cagA infection: evidence of an association

    DE Mattos


    Full Text Available Diseases resulting from Helicobacter pylori infection appear to be dependent on a host of genetic traits and virulence factors possessed by this microorganism. This paper aimed to investigate the association between the ABO histo-blood groups and H. pylori cagA infections. Genomic DNA samples (n = 110 of gastric biopsies obtained from patients with endoscopic diagnosis of peptic ulcers (n = 25 and chronic active gastritis (n = 85 were analyzed by PCR using specific primers for the cagA gene. Of the samples, 66.4% (n = 73 tested positive and 33.6% (n = 37 negative for the gene. The cagA strain was predominant in peptic ulcers (n = 21; 84.0% compared with chronic active gastritis (n = 52; 61.2% (p = 0.05; OR 3.332; 95% CI: 1.050-10.576. Additionally, the cagA strain was prevalent in the type O blood (48/63; 76.2% compared with other ABO phenotypes (25/47; 53.2% (p = 0.01; OR 2.816; 95% CI: 1.246-6.364. These results suggest that H. pylori cagA infection is associated with the O blood group in Brazilian patients suffering from chronic active gastritis and peptic ulcers.

  2. 反复胚胎种植失败患者HLA-Cw基因多态性的研究%Study on polymorphism of HLA-Cw in patients with repeated implantation failure

    王丽娟; 梁佩燕; 吴彤华; 李观贵; 陈晓燕; 尹彪; 曾勇


    目的 初探HLA-Cw基因多态性与反复胚胎种植失败的关系.方法 采用聚合酶链反应-直接碱基序列分析基因分型技术的方法对研究组50例反复胚胎种植失败患者和对照组17例一次体外受精-胚胎移植即获得妊娠并分娩活婴的患者进行HLA-Cw基因多态性检测,并采用SPSS17.0软件进行分析.结果 (1)在HLA-Cw01、HLA-Cw03、HLA-Cw07基因位点中,研究组和对照组均有较高的频率;(2)研究组HLA-Cw06基因频率较对照组高,HLA-Cw07基因频率低于对照组;(3)研究组和对照组的HLA-Cwasn频率远高于HLA-Cwlys;(4)研究组的HLA-Cwasn频率略低于对照组,HLA-Cwlys频率略高于对照组;(5)研究组夫妇双方均未检出HLA-Cwlys等位基因的比例较对照组低,而至少一方检出至少一个HLA-Cwlys等位基因的比例则较高.上述各观察指标两组间均无显著性差异(P>0.05).结论 HLA-Cwlys频率在反复胚胎种植失败患者中有增加趋势,虽无显著性差异,但有待扩大样本量进行进一步统计分析.%Objective: To investigate the correlation between the HLA-Cw gene polymorphism and the repeated implantation failure.Methods: Fifty patients with repeated implantation failure(study group)were matched to 17 patients who got pregnancy and had living birth from the first in vitro fertilization embryo transfer cycle (control group) . The genotyping of HLA-Cw gene detected by a polymerase chain reaction-sequence based genotyping(PCR-SBT)method. The data of the two groups was analyzed by the SPSS17. 0 software.Results: The results of both groups showed a high gene frequency in HLA-Cw * 01, HLA-Cw * 03 and HLA-Cw * 07. The gene frequency of HLA-Cw * 06 in the study group was higher than that in the control group. The gene frequency of HLA-Cw * 07 in the study group was lower than that in the control group. In both groups,their HLA-Cw asn frequency was much higher than HLA-Cw lys frequency. The study group had less HLA-Cw asn gene frequency

  3. Antibacterial activity of grape extracts on cagA-positive and -negative Helicobacter pylori clinical isolates.

    Martini, S; D'Addario, C; Braconi, D; Bernardini, G; Salvini, L; Bonechi, C; Figura, N; Santucci, A; Rossi, C


    There is considerable interest in alternative/adjuvant approaches for the eradication of Helicobacter pylori using biologically active compounds, especially antioxidants from plants. In the present work, we tested the antioxidant and antimicrobial activities of hydro-alcoholic extracts from Colorino, Sangiovese and Cabernet Sauvignon grape cultivars against H. pylori G21 (cagA-negative, cagA-) and 10K, (cagApositive, cagA+) clinical isolates. We determined the minimum bactericidal concentration (MBC) by incubating strain suspensions in Brucella broth with fetal bovine serum and samples at different concentrations in a final volume of 100 microl in a microaerobic atmosphere. After incubation, subcultures were carried out on Brucella agar plates which were incubated for 3-5 days in a microaerobic environment. The lowest concentration in broth, where the subculture on agar showed complete absence of growth, was considered the MBC.The Colorino extract showed the highest antibacterial activity against G21 strain (MBC=1.35 mg/ml), while Sangiovese and Carbernet MBCs were 4.0 mg/ml ca. H. pylori 10K was only susceptible to Colorino after 48 hours (MBC = 3.57 mg/ml). Resveratrol exhibited the highest antibacterial activity. interestingly, the most pathogenic strain (10K) was less susceptible to both the grape extracts and the isolated compounds. These results suggest that the administration of grape extracts and wine constituents, in addition to antibiotics, might be useful in the treatment of H. pylori infection. Should the reduced susceptibility of 10K strain be extended to all the cagA+ H. pylori isolates, which are endowed with cancer promoter activity, this observation may help explain why the organisms expressing CagA are more closely associated with atrophic gastritis and gastric carcinoma development. PMID:19933041

  4. A broad phenotypic screen identifies novel phenotypes driven by a single mutant allele in Huntington's disease CAG knock-in mice.

    Sabine M Hölter

    Full Text Available Huntington's disease (HD is an autosomal dominant neurodegenerative disorder caused by the expansion of a CAG trinucleotide repeat in the HTT gene encoding huntingtin. The disease has an insidious course, typically progressing over 10-15 years until death. Currently there is no effective disease-modifying therapy. To better understand the HD pathogenic process we have developed genetic HTT CAG knock-in mouse models that accurately recapitulate the HD mutation in man. Here, we describe results of a broad, standardized phenotypic screen in 10-46 week old heterozygous HdhQ111 knock-in mice, probing a wide range of physiological systems. The results of this screen revealed a number of behavioral abnormalities in HdhQ111/+ mice that include hypoactivity, decreased anxiety, motor learning and coordination deficits, and impaired olfactory discrimination. The screen also provided evidence supporting subtle cardiovascular, lung, and plasma metabolite alterations. Importantly, our results reveal that a single mutant HTT allele in the mouse is sufficient to elicit multiple phenotypic abnormalities, consistent with a dominant disease process in patients. These data provide a starting point for further investigation of several organ systems in HD, for the dissection of underlying pathogenic mechanisms and for the identification of reliable phenotypic endpoints for therapeutic testing.

  5. 18F-FDG PET uptake in the pre-Huntington disease caudate affects the time-to-onset independently of CAG expansion size

    To test in a longitudinal follow-up study whether basal glucose metabolism in subjects with a genetic risk of Huntington disease (HD) may influence the onset of manifest symptoms. The study group comprised 43 presymptomatic (preHD) subjects carrying the HD mutation. They underwent a 18F-FDG PET scan and were prospectively followed-up for at least 5 years using the unified HD rating scale to detect clinical changes. Multiple regression analysis included subject's age, CAG mutation size and glucose uptake as variables in a model to predict age at onset. Of the 43 preHD subjects who manifested motor symptoms, suggestive of HD, after 5 years from the PET scan, 26 showed a mean brain glucose uptake below the cut-off of 1.0493 in the caudate, significantly lower than the 17 preHD subjects who remained symptom-free (P < 0.0001). This difference was independent of mutation size. Measurement of brain glucose uptake improved the CAG repeat number and age-based model for predicting age at onset by 37 %. A reduced level of glucose metabolism in the brain caudate may represent a predisposing factor that contributes to the age at onset of HD in preHD subjects, in addition to the mutation size. (orig.)

  6. cagA positive Helicobacter pylori in Brazilian children related to chronic gastritis

    Luciano Lobo Gatti; Roger de Lábio; Luiz Carlos da Silva; Marília de Arruda Cardoso Smith; Spencer Luiz Marques Payão


    Helicobacter pylori is a spiral-shaped Gram-negative bacterium. It colonizes the gastric mucosa of humans and persists for decades if not treated. Helicobacter pylori infection affects more than half of the world's population and invariably results in chronic gastritis. The cagA gene is present in about 60 to 70% of H. pylori strains; it encodes a high-molecular-weight protein (120 to 140 kDa) and several investigators have noted a correlation between strains that possess cagA and the severit...

  7. L'erbario del Prof. Manlio Chiappini (1924-1998) in Herbarium CAG

    Curreli, Federica; Fogu, Maria Caterina


    The herbarium of Chiappini, held in Herbarium CAG of Cagliari University, is presented. Prof. Manlio Chiappini, who dead the 4th of january 1998, teached Botany at the Athenaeum of Cagliari from 1965 to 1987 and from 1965 to 1986 he was director of Botanical Institute and Botanical gardens of Cagliari University. From a research carried out in Herbarium CAG is shown that Chiappini’s herbarium is compound of 1262 exsiccata, referred to 630 specific and subspecific entities (about the 30% of Sa...

  8. Significant association of cagA positive Helicobacter pylori strains with risk of premature myocardial infarction

    Gunn, M.; Stephens, J.; Thompson, J.; Rathbone, B; Samani, N


    OBJECTIVE—To investigate whether genetic diversity of Helicobacter pylori influences its association with coronary heart disease, and specifically whether the risk is confined to infection with the more virulent strains bearing the cytotoxin associated gene-A (cagA) antigen.
DESIGN AND SETTING—Case-control study in hospital admitting unselected patients with myocardial infarction.
METHODS AND SUBJECTS—Serological status for cagA and H pylori were determined in 342 cases of acute myocardial in...

  9. CagA and VacA Helicobacter pylori antibodies in gastric cancer

    Suriani, Renzo; Colozza, Maurilio; Cardesi, Enrico; Mazzucco, Dario; Marino, Maria; Grosso, Silvia; Sanseverinati, Sabina; Venturini, Ivo; Borghi, Athos; Zeneroli, Maria Luisa


    BACKGROUND: Infection with different genotypes of virulent Helicobacter pylori strains (cytotoxin-associated gene A [CagA]-and/or vacuolating cytotoxin A [VacA]-positive) can play a role in the development of atrophic gastritis, duodenal ulcer (DU) and gastric cancer (GC).OBJECTIVE: To determine whether patients with GC and H pylori-negative histological staining had previously been infected with H pylori CagA- and/or VacA-positive virulent strains.METHODS: Twenty-three GC patients with a mea...

  10. Helicobacter pylori Infection in Thailand: A Nationwide Study of the CagA Phenotype.

    Tomohisa Uchida

    Full Text Available The risk to develop gastric cancer in Thailand is relatively low among Asian countries. In addition, the age-standardized incidence rate (ASR of gastric cancer in Thailand varies with geographical distribution; the ASR in the North region is 3.5 times higher than that in the South region. We hypothesized that the prevalence of H. pylori infection and diversity of CagA phenotype contributes to the variety of gastric cancer risk in various regions of Thailand.We conducted a nationwide survey within Thailand. We determined H. pylori infection prevalence by detecting H. pylori, using histochemical and immunohistochemical methods. The anti-CagA antibody and anti-East-Asian type CagA antibody (α-EAS Ab, which showed high accuracy in several East Asian countries, were used to determine CagA phenotype.Among 1,546 patients from four regions, including 17 provinces, the overall prevalence of H. pylori infection was 45.9% (710/1,546. Mirroring the prevalence of H. pylori infection, histological scores were the lowest in the South region. Of the 710 H. pylori-positive patients, 93.2% (662 were immunoreactive with the anti-CagA antibody. CagA-negative strain prevalence in the South region was significantly higher than that in other regions (17.9%; 5/28; p < 0.05. Overall, only 77 patients (11.6% were immunoreactive with the α-EAS Ab. There were no differences in the α-EAS Ab immunoreactive rate across geographical regions.This is the first study using immunohistochemistry to confirm H. pylori infections across different regions in Thailand. The prevalence of East-Asian type CagA H. pylori in Thailand was low. The low incidence of gastric cancer in Thailand may be attributed to the low prevalence of precancerous lesions. The low incidence of gastric cancer in the South region might be associated with the lower prevalence of H. pylori infection, precancerous lesions, and CagA-positive H. pylori strains, compared with that in the other regions.

  11. 短串联重复序列基因座与冲动暴力行为的关联研究%Association study of the genetic polymorphism of fifteen short tandem repeats loci and aggressive violent behavior

    杨春; 巴华杰; 高志勤; 赵汉清; 余海鹰; 施建安; 过伟


    目的 探讨冲动暴力行为与相关短串联重复序列基因座的关联情况.方法 运用AmpFISTR IdentifilerTM荧光标记复合扩增体系,对203例冲动暴力行为罪犯(研究组)与207名非暴力行为健康个体(对照组)样本进行聚合酶链反应复合扩增,然后应用ABI3100型基因分析系统对扩增产物进行电泳和基因检测,观察2组15个STR基因座等位基因及基因型频率的差异.结果 15个STR基因座均符合遗传平衡定律(Hardy-Weinberg定律);研究组与对照组THO1和TPOX基因座的等位基因频率分布的差异有统计学意义(P<0.05);研究组和对照组THO1-10频率分别为0.0172和0.0580,差异有统计学意义(P=0.002,OR=0.29,95% CI:0.12 ~0.67);研究组和对照组TPOX-11频率分别为0.3621和0.2391,差异有统计学意义(P=0.000,OR=1.81,95% CI:1.33 ~ 2.45);其他STR基因座等位基因频率及所有基因型频率2组差异均无统计学意义(P>0.05).结论 THO1和TPOX基因座多态性与冲动暴力行为可能存在关联,等位基因THO1-10、TPOX-11与冲动暴力行为的发生可能有一定关系.%Objective To investigate the association of aggressive violent behavior and related short tandem repeats (STRs) loci by the analysis of 15 STRs loci genetic polymorphism.Methods The biological samples of 203 persons with aggressive violent behaviors and 207 healthy persons without violent behavior were collected.Then the DNA sample was amplified by AmpFISTR IdentifilerTM system and separated by electrophoresis to compare the genotypes and alleles of 15 STRs gene frequencies in the two groups.Results All the 15 STRs loci in people with aggressive violent behavior and healthy people were found to coincide with Hardy-Weinberg equilibrium ( P > 0.05 ).There was a significant difference in distributing of allele frequency of THO1 and TPOX between people with aggressive violent behaviors and healthy people ( P < 0.05 ).The frequency of allele 10 of THO1

  12. Family Polymorphism

    Ernst, Erik


    safety and flexibility at the level of multi-object systems. We are granted the flexibility of using different families of kinds of objects, and we are guaranteed the safety of the combination. This paper highlights the inability of traditional polymorphism to handle multiple objects, and presents family...... polymorphism as a way to overcome this problem. Family polymorphism has been implemented in the programming language gbeta, a generalized version of Beta, and the source code of this implementation is available under GPL....

  13. Clinical significance of infection with cag A and vac A positive helicobacter pylori strains

    Sokić-Milutinović Aleksandra


    Full Text Available Clinical relevance of infection with different Helicobacter pylori strains was reviewed in this paper. Helicobacter pylori (H. pylori infection plays a role in pathogenesis of chronic gastritis, peptic ulcer disease, gastric adenocarcinoma and MALT lymphoma. Extragastric manifestations of H. pylori infection most probably include acne rosacea and chronic urticaria, while the importance of H. pylori infection for pathogenesis of growth retardation in children, iron deficiency anemia, coronary heart disease, stroke and idiopathic thrombocytopenic purpura remains vague. The expression of two H. pylori proteins, cytotoxin associated protein (cag A and vacuolization cytotoxin (vac A is considered to be related with pathogenicity of the bacterium. It is clear that presence of cag A+ strains is important for development of peptic ulcer; nevertheless, it is also protective against esophageal reflux disease. On the other hand, cag A+ strains are common in gastric adenocarcinoma and MALT lymphoma patients, but it seems that certain subtypes of vac A cytotoxin are more important risk factors. Infection with cag A+ strains is more common in patients with acne rosacea, stroke and coronary heart disease.

  14. Diverse Characteristics of the cagA Gene of Helicobacter pylori Strains Collected from Patients from Southern Vietnam with Gastric Cancer and Peptic Ulcer▿

    Truong, Bui Xuan; Mai, Vo Thi Chi; Hiroshi TANAKA; Ly, Le Thanh; Thong, Tran Minh; Hai, Hoang Hoa; Van Long, Dao; Furumatsu, Keisuke; Yoshida, Masaru; Kutsumi, Hiromu; Azuma, Takeshi


    The pathogenesis of gastroduodenal diseases is related to the diversity of Helicobacter pylori strains. CagA-positive strains are more likely to cause gastric cancer than CagA-negative strains. Based on EPIYA (Glu-Pro-Ile-Tyr-Ala) motifs at the carboxyl terminus corresponding to phosphorylation sites, H. pylori CagA is divided into East Asian CagA and Western CagA. The former type prevails in East Asia and is more closely associated with gastric cancer. The present study used full sequences o...

  15. Induction of CD69 expression by cagPAI-positive Helicobacter pylori infection

    Naoki Mori; Chie Ishikawa; Masachika Senba


    AIM: To investigate and elucidate the molecular mech-anism that regulates inducible expression of CD69 by Helicobacter pylori (H. pylori ) infection.METHODS: The expression levels of CD69 in a T-cell line, Jurkat, primary human peripheral blood mononu-clear cells (PBMCs), and CD4+T cells, were assessed by immunohistochemistry, reverse transcription polymerase chain reaction, and flow cytometry. Activation of CD69 promoter was detected by reporter gene. Nuclear factor (NF)-κB activation in Jurkat cells infected with H. pylori was evaluated by electrophoretic mobility shift assay. The role of NF-κB signaling in H. pylori -induced CD69 expression was analyzed using inhibitors of NF-κB and dominant-negative mutants. The isogenic mutants with disrupted cag pathogenicity island ( cagPAI) and virD4 were used to elucidate the role of cagPAI-encoding type Ⅳ secretion system and CagA in CD69 expression.RESULTS: CD69 staining was detected in mucosal lymphocytes and macrophages in specimens of pa-tients with H. pylori -positive gastritis. Although cagPAI-positive H. pylori and an isogenic mutant of virD4 induced CD69 expression, an isogenic mutant of cag-PAI failed to induce this in Jurkat cells. H. pylori also induced CD69 expression in PBMCs and CD4+T cells. The activation of the CD69 promoter by H. pylori was mediated through NF-κB. Transfection of dominant-negative mutants of IκBs, IκB kinases, and NF-κB-inducing kinase inhibited H. pylori -induced CD69 activation. Inhibitors of NF-κB suppressed H. pylori -induced CD69 mRNA expression.CONCLUSION: The results suggest that H. pylori in-duces CD69 expression through the activation of NF-κB. cagPAI might be relevant in the induction of CD69 expression in T cells. CD69 in T cells may play a role in H. pylori -induced gastritis.

  16. Quantitative analysis of CagA type IV secretion by Helicobacter pylori reveals substrate recognition and translocation requirements.

    Schindele, Franziska; Weiss, Evelyn; Haas, Rainer; Fischer, Wolfgang


    Bacterial type IV secretion systems are protein transporters with a remarkable diversity of substrates and substrate recognition mechanisms. Type IV-secreted proteins often contain C-terminal secretion signals, but may also require other regions for recognition as secretory substrates, or for full secretion efficiency. For example, type IV secretion of CagA, a major pathogenicity factor of the human gastric pathogen Helicobacter pylori, depends on a C-terminal signal and on N-terminal protein regions. To examine the involvement of individual CagA regions for type IV secretion efficiency, we have established and evaluated a β-lactamase-dependent reporter system which allows quantitative determination of translocation into host cells. For validation, we used this reporter system to obtain quantitative data for type IV secretion of CagA variants with sequential C-terminal truncations. Alanine-scanning mutagenesis of the CagA C-terminus revealed that none of the characteristic charged residues in this region is necessary for type IV secretion. Translocation rates measured for CagA variants with N-terminal deletions show that CagA does not have an N-terminal signal sequence, but requires its N-terminal domain for efficient secretion. Finally, we provide evidence that only newly synthesized CagA protein is translocated, supporting a model in which type IV secretion is coupled to protein biosynthesis. PMID:26713727

  17. A transgenic Drosophila model demonstrates that the Helicobacter pylori CagA protein functions as a eukaryotic Gab adaptor.

    Crystal M Botham


    Full Text Available Infection with the human gastric pathogen Helicobacter pylori is associated with a spectrum of diseases including gastritis, peptic ulcers, gastric adenocarcinoma, and gastric mucosa-associated lymphoid tissue lymphoma. The cytotoxin-associated gene A (CagA protein of H. pylori, which is translocated into host cells via a type IV secretion system, is a major risk factor for disease development. Experiments in gastric tissue culture cells have shown that once translocated, CagA activates the phosphatase SHP-2, which is a component of receptor tyrosine kinase (RTK pathways whose over-activation is associated with cancer formation. Based on CagA's ability to activate SHP-2, it has been proposed that CagA functions as a prokaryotic mimic of the eukaryotic Grb2-associated binder (Gab adaptor protein, which normally activates SHP-2. We have developed a transgenic Drosophila model to test this hypothesis by investigating whether CagA can function in a well-characterized Gab-dependent process: the specification of photoreceptors cells in the Drosophila eye. We demonstrate that CagA expression is sufficient to rescue photoreceptor development in the absence of the Drosophila Gab homologue, Daughter of Sevenless (DOS. Furthermore, CagA's ability to promote photoreceptor development requires the SHP-2 phosphatase Corkscrew (CSW. These results provide the first demonstration that CagA functions as a Gab protein within the tissue of an organism and provide insight into CagA's oncogenic potential. Since many translocated bacterial proteins target highly conserved eukaryotic cellular processes, such as the RTK signaling pathway, the transgenic Drosophila model should be of general use for testing the in vivo function of bacterial effector proteins and for identifying the host genes through which they function.

  18. Isolation and Characterization of 46 Novel Polymorphic EST-Simple Sequence Repeats (SSR Markers in Two Sinipercine Fishes (Siniperca and Cross-Species Amplification

    Liang Cao


    Full Text Available With the development of next generation sequencing technologies, transcriptome level sequence collections are emerging as prominent resources for the discovery of gene-based molecular markers. In this study, we described the isolation and characterization of 46 novel polymorphic microsatellite loci for Siniperca chuatsi and Siniperca scherzeri from the transcriptome of their F1 interspecies hybrids. Forty-three of these loci were polymorphic in S. chuatsi, and 20 were polymorphic in S. scherzeri. In S. chuatsi, the number of alleles per locus ranged from 2 to 8, and the observed and expected heterozygosities varied from 0.13 to 1.00 and from 0.33 to 0.85, respectively. In S. scherzeri, the number of alleles per locus ranged from 3 to 9, and the observed and expected heterozygosities varied from 0.19 to 1.00 and from 0.28 to 0.88, respectively. We also evaluated the cross-amplification of 46 polymorphic loci in four species of sinipercine fishes: Siniperca kneri, Siniperca undulata, Siniperca obscura, and Coreoperca whiteheadi. The interspecies cross-amplification rate was very high, totaling 94% of the 184 locus/taxon combinations tested. These markers will be a valuable resource for population genetic studies in sinipercine fishes.

  19. Variation in number of cagA EPIYA-C phosphorylation motifs between cultured Helicobacter pylori and biopsy strain DNA

    Karlsson, Anneli; Ryberg, Anna; Nosouhi Dehnoei, Marjan; Borch, Kurt; Monstein, Hans-Jürg


    The Helicobacter pylori cagA gene encodes a cytotoxin which is activated by phosphorylation after entering the host epithelial cell. Phosphorylation occurs on specific tyrosine residues within EPIYA motifs in the variable 3'-region. Four different cagA EPIYA motifs have been defined according to the surrounding amino acid sequence; EPIYA-A, -B, -C and -D. Commonly, EPIYA-A and -B are followed by one or more EPIYA-C or -D motif. Due to observed discrepancies in cagA genotypes in cultured H. py...

  20. High Prevalence of cagA- and babA2-Positive Helicobacter pylori Clinical Isolates in Taiwan

    Lai, Chih-Ho; Kuo, Chun-Hsien; Chen, Ya-Chi; Chao, Fang-Yu; Poon, Sek-Kwong; Chang, Chi-Sen; Wang, Wen-Ching


    Two virulence markers, cagA and babA2, were characterized by PCR in 101 Helicobacter pylori isolates from a population in Taiwan. cagA was detected in 99% of the isolates, while babA2 was present in all of the isolates. Base deletions and substitutions at the forward babA2 primer annealing sites were found. Given their high prevalence, cagA and babA2 cannot be useful markers for predicting the high-risk patients of H. pylori infection in Taiwan.

  1. Differentiation of Strains of Xylella fastidiosa by a Variable Number of Tandem Repeat Analysis

    Coletta-Filho, Helvécio Della; Takita, Marco Aurélio; de Souza, Alessandra Alves; Aguilar-Vildoso, Carlos Ivan; Machado, Marcos Antonio


    Short sequence repeats (SSRs) with a potential variable number of tandem repeat (VNTR) loci were identified in the genome of the citrus pathogen Xylella fastidiosa and used for typing studies. Although mono- and dinucleotide repeats were absent, we found several intermediate-length 7-, 8-, and 9-nucleotide repeats, which we examined for allelic polymorphisms using PCR. Five genuine VNTR loci were highly polymorphic within a set of 27 X. fastidiosa strains from different hosts. The highest ave...

  2. HA novel approach to investigate tissue-specific trinucleotide repeat instability

    Boily Marie-Josee


    Full Text Available Abstract Background In Huntington's disease (HD, an expanded CAG repeat produces characteristic striatal neurodegeneration. Interestingly, the HD CAG repeat, whose length determines age at onset, undergoes tissue-specific somatic instability, predominant in the striatum, suggesting that tissue-specific CAG length changes could modify the disease process. Therefore, understanding the mechanisms underlying the tissue specificity of somatic instability may provide novel routes to therapies. However progress in this area has been hampered by the lack of sensitive high-throughput instability quantification methods and global approaches to identify the underlying factors. Results Here we describe a novel approach to gain insight into the factors responsible for the tissue specificity of somatic instability. Using accurate genetic knock-in mouse models of HD, we developed a reliable, high-throughput method to quantify tissue HD CAG repeat instability and integrated this with genome-wide bioinformatic approaches. Using tissue instability quantified in 16 tissues as a phenotype and tissue microarray gene expression as a predictor, we built a mathematical model and identified a gene expression signature that accurately predicted tissue instability. Using the predictive ability of this signature we found that somatic instability was not a consequence of pathogenesis. In support of this, genetic crosses with models of accelerated neuropathology failed to induce somatic instability. In addition, we searched for genes and pathways that correlated with tissue instability. We found that expression levels of DNA repair genes did not explain the tissue specificity of somatic instability. Instead, our data implicate other pathways, particularly cell cycle, metabolism and neurotransmitter pathways, acting in combination to generate tissue-specific patterns of instability. Conclusion Our study clearly demonstrates that multiple tissue factors reflect the level of

  3. P53 codon 11, 72, and 248 gene polymorphisms in endometriosis

    Hsieh, Yao-Yuan; Lin, Chich-Sheng


    Objective: Mutated p53 gene is related to the instability of cell growth and cell cycle progression. We aimed to evaluate the association between endometriosis and p53 codon 11, 72 and 248 gene polymorphisms. Patients and methods: Women were divided into two groups: (1) moderate/severe endometriosis (n=148), and (2) non-endometriosis groups (n=150). P53 gene polymorphisms include codon11 Glu/Gln or Lys (GAG->CAG or AAG), codon 72 Arg/Pro (CGC->CCC), and codon 248 Arg/Thr (CGG->TCG). These gen...

  4. Determination of strains of Helicobacter pylori and of polymorphism in the interleukin-8 gene in patients with stomach cancer

    Ruth Maria Dias Ferreira Vinagre


    Full Text Available CONTEXT: Gastric neoplasia is the second most common cause of death by cancer in the world and H. pylori is classified as a type I human carcinogen by the World Health Organization. However, despite the high prevalence of infection by H. pylori around the world, less than 3% of individuals carrying the bacteria develop gastric neoplasias. Such a fact indicates that evolution towards malignancy may be associated with bacterial factors in the host and the environment. OBJECTIVES: To investigate the association between polymorphism in the region promoting the IL-8 (-251 gene and the H. pylori genotype, based on the vacA alleles and the presence of the cagA gene, using clinical and histopathological data. METHODS: In a prospective study, a total of 102 patients with stomach cancer and 103 healthy volunteers were analysed. Polymorphism in interleukin 8 (-251 was determined by the PCR-restriction fragment length polymorphism reaction and sequencing. PCR was used for genotyping the vacA alleles and the cagA in the bacterial strains PCR. Gastric biopsies were histologically assessed. RESULTS: The H. pylori serology was positive for 101 (99% of all patients analysed, and 98 (97% of them were colonized by only one strain. In patients with monoinfection, 82 (84% of the bacterial strains observed had the s1b/m1 genotype. The cagA gene was detected in 74 (73% of patients infected by H. pylori. The presence of the cagA gene was demonstrated as associated with the presence of the s1b/m1 genotype of the vacA gene (P = 0.002. As for polymorphism in the interleukin 8 (-251 gene we observed that the AA (P = 0.026 and AT (P = 0.005 genotypes were most frequent in the group of patients with gastric adenocarcinoma. By comparing the different types of isolated bacterial strains with the interleukin -8 (-251 and the histopathological data we observed that carriers of the A allele (AT and AA infected by virulent strains (m1s1 cagA+ demonstrated a greater risk of

  5. Short QTc Interval in Males with Klinefelter Syndrome-Influence of CAG Repeat Length, Body Composition, and Testosterone Replacement Therapy

    Jørgensen, Inger Norlyk; Skakkebaek, Anne; Andersen, Niels Holmark; Pedersen, Lisbeth Nørum; Hougaard, David Michael; Bojesen, Anders; Trolle, Christian; Gravholt, Claus Højbjerg


    BackgroundKlinefelter syndrome (KS) is a sex chromosomal aneuploidy (47,XXY) affecting 1/660 males. Based on findings in Turner syndrome, we hypothesized that electrocardiogram (ECG) abnormalities would be present in males with KS. ObjectiveTo investigate ECGs in males with KS and compare with co...

  6. Androgen receptor gene CAG repeat length as modifier of the association between Persistent Organohalogen Pollutant exposure markers and semen characteristics

    Giwercman, Aleksander; Rylander, Lars; Rignell-Hydbom, Anna;


    OBJECTIVES: Exposure to persistent organohalogen pollutants was suggested to impair male reproductive function. A gene-environment interaction has been proposed. No genes modifying the effect of persistent organohalogen pollutants on reproductive organs have yet been identified. We aimed to inves...

  7. CagA+ H pylori infection is associated with polarization of T helper cell immune responses in gastric carcinogenesis

    Shu-Kui Wang; Hui-Fang Zhu; Bang-Shun He; Zhen-Yu Zhang; Zhi-Tan Chen; Zi-Zheng Wang; Guan-Ling Wu


    AIM: To characterize the immune responses including local and systemic immunity induced by infection with H pylori, especially with CagA+ H pylori strains and the underlying immunopathogenesis.METHODS: A total of 711 patients with different gastric lesions were recruited to determine the presence of H pylori infection and cytotoxin associated protein A (CagA), the presence of T helper (Th) cells and regulatory T (Treg)cells in peripheral blood mononuclear cells (PBMCs),expression of plasma cytokines, and RNA and protein expression of IFN-γ and IL-4 in gastric biopsies and PBMCs were determined by rapid urease test, urea [14C]breath test, immunoblotting test, flow cytometry, real time RT-PCR and immunohistochemistry.RESULTS: Of the patients, 629 (88.47%) were infected with H pylori; 506 (71.16%) with CagA+ and 123 (17.30%) with CagA- strains. Among patients infected with CagA+ H pylori strains, Th1-mediated cellular immunity was associated with earlier stages of gastric carcinogenesis, while Th2-mediated humoral immunity dominated the advanced stages and was negatively associated with an abundance of Treg cells. However,there was no such tendency in Th1/Th2 polarization in patients infected with CagA- H pylori strains and those without H pylori infection,CONCLUSION: Polarization of Th cell immune responses occurs in patients with CagA+ H pylori infection, which is associated with the stage and severity of gastric pathology during the progression of gastric carcinogenesis. This finding provides further evidence for a causal role of CagA+ H pylori infection in the immunopathogenesis of gastric cancer.

  8. Assessment of East Asian-type cagA-positive Helicobacter pylori using stool specimens from asymptomatic healthy Japanese individuals.

    Hirai, Itaru; Sasaki, Tadahiro; Kimoto, Ai; Fujimoto, Saori; Moriyama, Toshiki; Yamamoto, Yoshimasa


    Recent investigations have suggested that CagA, a virulence factor of Helicobacter pylori and known to have multiple genotypes, plays a critical role in the development of stomach cancer. However, the prevalence of cagA-positive H. pylori strains and the cagA genotypes have not been well studied in healthy individuals because of the difficulty in collecting gastric specimens. In the present study, we assessed the prevalence of infection with H. pylori, particularly the strains with the East Asian cagA genotype (which is more potent in causing gastric diseases), among healthy asymptomatic Japanese individuals by a noninvasive method using stool specimens. The H. pylori antigen was detected in 40.3 % of healthy asymptomatic adult individuals (n=186) enrolled in the study. For the detection and genotyping of the cagA gene, DNA was extracted from the stool specimens of these individuals and analysed by PCR. We detected the East Asian cagA genotype in the DNA samples of a significantly high number (63.1 %) of healthy asymptomatic Japanese individuals. These results indicate that a significant number of asymptomatic healthy Japanese individuals were infected with highly virulent H. pylori. PMID:19528144

  9. The Helicobacter pylori cytotoxin CagA is essential for suppressing host heat shock protein expression.

    J Lang, Ben; J Gorrell, Rebecca; Tafreshi, Mona; Hatakeyama, Masanori; Kwok, Terry; T Price, John


    Bacterial infections typically elicit a strong Heat Shock Response (HSR) in host cells. However, the gastric pathogen Helicobacter pylori has the unique ability to repress this response, the mechanism of which has yet to be elucidated. This study sought to characterize the underlying mechanisms by which H. pylori down-modulates host HSP expression upon infection. Examination of isogenic mutant strains of H. pylori defective in components of the type IV secretion system (T4SS), identified the secretion substrate, CagA, to be essential for down-modulation of the HSPs HSPH1 (HSP105), HSPA1A (HSP72), and HSPD1 (HSP60) upon infection of the AGS gastric adenocarcinoma cell line. Ectopic expression of CagA by transient transfection was insufficient to repress HSP expression in AGS or HEK293T cells, suggesting that additional H. pylori factors are required for HSP repression. RT-qPCR analysis of HSP gene expression in AGS cells infected with wild-type H. pylori or isogenic cagA-deletion mutant found no significant change to account for reduced HSP levels. In summary, this study identified CagA to be an essential bacterial factor for H. pylori-mediated suppression of host HSP expression. The novel finding that HSPH1 is down-modulated by H. pylori further highlights the unique ability of H. pylori to repress the HSR within host cells. Elucidation of the mechanism by which H. pylori achieves HSP repression may prove to be beneficial in the identification of novel mechanisms to inhibit the HSR pathway and provide further insight into the interactions between H. pylori and the host gastric epithelium. PMID:26928021

  10. Triplet repeat DNA structures and human genetic disease: dynamic mutations from dynamic DNA

    Richard R Sinden; Vladimir N Potaman; Elena A Oussatcheva; Christopher E Pearson; Yuri L Lyubchenko; Luda S Shlyakhtenko


    Fourteen genetic neurodegenerative diseases and three fragile sites have been associated with the expansion of (CTG)n•(CAG)n, (CGG)n•(CCG)n, or (GAA)n•(TTC)n repeat tracts. Different models have been proposed for the expansion of triplet repeats, most of which presume the formation of alternative DNA structures in repeat tracts. One of the most likely structures, slipped strand DNA, may stably and reproducibly form within triplet repeat sequences. The propensity to form slipped strand DNA is proportional to the length and homogeneity of the repeat tract. The remarkable stability of slipped strand DNA may, in part, be due to loop-loop interactions facilitated by the sequence complementarity of the loops and the dynamic structure of three-way junctions formed at the loop-outs.

  11. How valid is single nucleotide polymorphism (SNP) diagnosis for the individual risk assessment of breast cancer?

    Tempfer, Clemens B; Hefler, Lukas A; Schneeberger, Christian; Huber, Johannes C


    The number of reports investigating disease susceptibility based on the carriage of low-penetrance, high-frequency single nucleotide polymorphisms (SNPs) has increased in recent years. Evidence is accumulating defining specific individual variations in breast cancer susceptibility. Genetic variations of estradiol and xenobiotics metabolisms as well as genes involved in cell-cycle control have been described as significant contributors to breast cancer susceptibility, with variations depending on ethnic background and co-factors such as smoking and family history of breast cancer. In sum, the highest level of evidence to date linking SNPs and breast cancer comes from nested case-control studies within the prospective Nurses' Health Study. These data establish seven SNPs - hPRB +331G/A, AR CAG repeat, CYP19 (TTTA)10, CYP1A1 MspI, VDR FOK1, XRCC1 Arg194Trp and XRCC2 Arg188His - as small but significant risk factors for spontaneous, non-hereditary breast cancer. In addition, meta-analysis of data in the literature establishes the TGFBR1*6A, HRAS1, GSTP Ile105Val and GSTM1 SNPs as low-penetrance genetic risk factors of sporadic breast cancer. The clinical consequences of such a risk elevation may be detailed instruction of the patient as to general measures of breast cancer prevention such as a low-fat diet, optimization of body mass index, physical exercise, avoidance of alcohol and long-term hormone replacement therapy, and participation in a breast cancer screening program between the ages of 50 and 70 years. Specific surgical or drug interventions such as prophylactic mastectomy and oophorectomy or prophylactic intake of tamoxifen are not indicated based on SNP analysis at this time. PMID:16835078

  12. Triplet repeat length bias and variation in the human transcriptome

    Molla, Michael; Delcher, Arthur; Sunyaev, Shamil; Cantor, Charles; Kasif, Simon


    Length variation in short tandem repeats (STRs) is an important family of DNA polymorphisms with numerous applications in genetics, medicine, forensics, and evolutionary analysis. Several major diseases have been associated with length variation of trinucleotide (triplet) repeats including Huntington's disease, hereditary ataxias and spinobulbar muscular atrophy. Using the reference human genome, we have catalogued all triplet repeats in genic regions. This data revealed a bias in noncoding D...

  13. Ataxin-2 repeat-length variation and neurodegeneration

    Ross, Owen A.; Rutherford, Nicola J.; Baker, Matt; Soto-Ortolaza, Alexandra I.; Carrasquillo, Minerva M.; DeJesus-Hernandez, Mariely; Adamson, Jennifer; Li, Ma; Volkening, Kathryn; Finger, Elizabeth; Seeley, William W.; Hatanpaa, Kimmo J.; Lomen-Hoerth, Catherine; Kertesz, Andrew; Bigio, Eileen H


    Expanded glutamine repeats of the ataxin-2 (ATXN2) protein cause spinocerebellar ataxia type 2 (SCA2), a rare neurodegenerative disorder. More recent studies have suggested that expanded ATXN2 repeats are a genetic risk factor for amyotrophic lateral sclerosis (ALS) via an RNA-dependent interaction with TDP-43. Given the phenotypic diversity observed in SCA2 patients, we set out to determine the polymorphic nature of the ATXN2 repeat length across a spectrum of neurodegenerative disorders. In...

  14. CagA, a major virulence factor of Helicobacter pylori, promotes the production and underglycosylation of IgA1 in DAKIKI cells

    Yang, Man [Department of Nephrology, The First Affiliated Hospital of Chengdu Medical College, Chengdu City 610500 (China); Li, Fu-gang [Department of Nephrology, Affiliated Hospital of Luzhou Medical College, Luzhou City 646000 (China); Xie, Xi-sheng [Department of Nephrology, Second Clinical Medical Institution of North Sichuan Medical College (Nanchong Central Hospital), Nanchong City 637400 (China); Wang, Shao-qing [Department of Nephrology, The First Affiliated Hospital of Chengdu Medical College, Chengdu City 610500 (China); Fan, Jun-ming, E-mail: [Department of Nephrology, The First Affiliated Hospital of Chengdu Medical College, Chengdu City 610500 (China); Department of Nephrology, Affiliated Hospital of Luzhou Medical College, Luzhou City 646000 (China)


    Highlights: • CagA stimulated cell proliferation and the production of IgA1 in DAKIKI cells. • CagA promoted the underglycosylation of IgA1 in DAKIKI cells. • CagA decreased the expression of C1GALT1 and its chaperone Cosmc in DAKIKI cells. • Helicobacter pylori infection may participate in the pathogenesis of IgAN via CagA. - Abstract: While Helicobacter pylori (Hp) infection is closely associated with IgA nephropathy (IgAN), the underlying molecular mechanisms remain to be elucidated. This study was to investigate the effect of cytotoxin associated gene A protein (CagA), a major virulence factor of Hp, on the production and underglycosylation of IgA1 in the B cell line DAKIKI cells. Cells were cultured and treated with recombinant CagA protein. We found that CagA stimulated cell proliferation and the production of IgA1 in a dose-dependent and time-dependent manner. Moreover, CagA promoted the underglycosylation of IgA1, which at least partly attributed to the downregulation of β1,3-galactosyltransferase (C1GALT1) and its chaperone Cosmc. In conclusion, we demonstrated that Hp infection, at least via CagA, may participate in the pathogenesis of IgAN by influencing the production and glycosylation of IgA1 in B cells.

  15. Prevalence and Correlation with Clinical Diseases of Helicobacter pylori cagA and vacA Genotype among Gastric Patients from Northeast China


    Helicobacter pylori vacA and cagA genes have significant genetic heterogenicity, resulting in different clinical outcomes. Northeast part of China has reported high prevalence of H. pylori infections and gastric cancer. Hence, we investigated the H. pylori cagA and vacA genotypes with clinical outcomes in Northeast China. Gastric tissue samples (n = 169), chronic gastritis (GIs), gastric ulcer (GU), and gastric cancer (GC) were analysed for 16S rRNA ureA, cagA, and cagA genotypes by PCR. A to...

  16. Role of Helicobacter pylori cagA EPIYA motif and vacA genotypes for the development of gastrointestinal diseases in Southeast Asian countries: a meta-analysis

    Sahara Shu; Sugimoto Mitsushige; Vilaichone Ratha-Korn; Mahachai Varocha; Miyajima Hiroaki; Furuta Takahisa; Yamaoka Yoshio


    Abstract Background Infection with cagA-positive, cagA EPIYA motif ABD type, and vacA s1, m1, and i1 genotype strains of Helicobacter pylori is associated with an exacerbated inflammatory response and increased risk of gastroduodenal diseases. However, it is unclear whether the prevalence and virulence factor genotypes found in Southeast Asia are similar to those in Western countries. Here, we examined the cagA status and prevalence of cagA EPIYA motifs and vacA genotypes among H. pylori stra...

  17. CagA, a major virulence factor of Helicobacter pylori, promotes the production and underglycosylation of IgA1 in DAKIKI cells

    Highlights: • CagA stimulated cell proliferation and the production of IgA1 in DAKIKI cells. • CagA promoted the underglycosylation of IgA1 in DAKIKI cells. • CagA decreased the expression of C1GALT1 and its chaperone Cosmc in DAKIKI cells. • Helicobacter pylori infection may participate in the pathogenesis of IgAN via CagA. - Abstract: While Helicobacter pylori (Hp) infection is closely associated with IgA nephropathy (IgAN), the underlying molecular mechanisms remain to be elucidated. This study was to investigate the effect of cytotoxin associated gene A protein (CagA), a major virulence factor of Hp, on the production and underglycosylation of IgA1 in the B cell line DAKIKI cells. Cells were cultured and treated with recombinant CagA protein. We found that CagA stimulated cell proliferation and the production of IgA1 in a dose-dependent and time-dependent manner. Moreover, CagA promoted the underglycosylation of IgA1, which at least partly attributed to the downregulation of β1,3-galactosyltransferase (C1GALT1) and its chaperone Cosmc. In conclusion, we demonstrated that Hp infection, at least via CagA, may participate in the pathogenesis of IgAN by influencing the production and glycosylation of IgA1 in B cells

  18. A yeast tRNA mutant that causes pseudohyphal growth exhibits reduced rates of CAG codon translation.

    Kemp, Alain J; Betney, Russell; Ciandrini, Luca; Schwenger, Alexandra C M; Romano, M Carmen; Stansfield, Ian


    In Saccharomyces cerevisiae, the SUP70 gene encodes the CAG-decoding tRNA(Gln)(CUG). A mutant allele, sup70-65, induces pseudohyphal growth on rich medium, an inappropriate nitrogen starvation response. This mutant tRNA is also a UAG nonsense suppressor via first base wobble. To investigate the basis of the pseudohyphal phenotype, 10 novel sup70 UAG suppressor alleles were identified, defining positions in the tRNA(Gln)(CUG) anticodon stem that restrict first base wobble. However, none conferred pseudohyphal growth, showing altered CUG anticodon presentation cannot itself induce pseudohyphal growth. Northern blot analysis revealed the sup70-65 tRNA(Gln)(CUG) is unstable, inefficiently charged, and 80% reduced in its effective concentration. A stochastic model simulation of translation predicted compromised expression of CAG-rich ORFs in the tRNA(Gln)(CUG)-depleted sup70-65 mutant. This prediction was validated by demonstrating that luciferase expression in the mutant was 60% reduced by introducing multiple tandem CAG (but not CAA) codons into this ORF. In addition, the sup70-65 pseudohyphal phenotype was partly complemented by overexpressing CAA-decoding tRNA(Gln)(UUG), an inefficient wobble-decoder of CAG. We thus show that introducing codons decoded by a rare tRNA near the 5' end of an ORF can reduce eukaryote translational expression, and that the mutant tRNA(CUG)(Gln) constitutive pseudohyphal differentiation phenotype correlates strongly with reduced CAG decoding efficiency. PMID:23146061

  19. The frequency of Helicobacter pylor infection and cagA expression in the Korean patients with gastric carcinoma

    Helicobacter pylori infection had been approved as a group 1 carcinogen by the international agency for research on cancer. However the association between H.pylori infection and gastric carcinoma was not so definite in South Asia including Korea, and the role of cagA gene of H.pylori in gastric carcinogenesis was a controversial issue. The aims of this study were firstly to study in vivo expression frequency of 16S rRNA and cagA gene of H.pylori, secondly to study the association between H.pylori infection and gastric cancer, the association between cagA expression and gastric cancer in Korean patients. In vivo expression rate of 16S rRNA was 74 % of gastric carcinoma patients and cagA expression rate was 51 % of gastric carcinoma patients with H.pylori infection. Although 90 % of gastric carcinoma patients had H.pylori infection, the association between H.pylori infection and gastric carcinoma was not significant. And there was no significant association between cagA expression and gastric carcinoma. (author). 37 refs., 2 tabs., 1 fig

  20. An inverse relationship between CagA+ strains of Helicobacter pylori infection and risk of erosive GERD

    The aim of this study is investigating the association of Helicobacter pylori (H. pylori) infection and its cytogenetic-associated gene A (cag A) strain with reflux esophagitis. In a case-control setting (May 2005-2006), patients with reflux esophagitis (case group) were compared with age and gender matched people suffering from symptoms of gastroesophageal reflux disease with normal upper gastrointestinal endoscopic findings (control group) in Imam Khomeini Hospital, Tabriz, Iran. The rates of H. pylori and its cagA positive infections were separately compared between the 2 groups and the subgroups with different severity of reflux esophagitis. Ninety-two and 93 patients were enrolled in the case and control groups. The rate of H.pylori infection was significantly lower in case group (81.5%versus 87.10%, p=0.29, odd ratio 0.654, 95% confidence interval [CI] 0.293 to 1.495). The CagA positive infections were found significantly more frequent in the control group (59.1% versus 40.2%, p=0.01, odd ratio 0.465, 95% CI 0.258 to 0.836). There was no significant difference between the severity subgroups of the disease for H. pylori (p=0.30) or cagA positive infection rates (p=0.40). The cagA positive strains might have a protective effect against reflux esophagitis. (author)

  1. The frequency of Helicobacter pylor infection and cagA expression in the Korean patients with gastric carcinoma

    Jung, Sook Hyang; Kim, Yoo Chul [Korea Cancer Center Hospital, Seoul (Korea, Republic of)


    Helicobacter pylori infection had been approved as a group 1 carcinogen by the international agency for research on cancer. However the association between H.pylori infection and gastric carcinoma was not so definite in South Asia including Korea, and the role of cagA gene of H.pylori in gastric carcinogenesis was a controversial issue. The aims of this study were firstly to study in vivo expression frequency of 16S rRNA and cagA gene of H.pylori, secondly to study the association between H.pylori infection and gastric cancer, the association between cagA expression and gastric cancer in Korean patients. In vivo expression rate of 16S rRNA was 74 % of gastric carcinoma patients and cagA expression rate was 51 % of gastric carcinoma patients with H.pylori infection. Although 90 % of gastric carcinoma patients had H.pylori infection, the association between H.pylori infection and gastric carcinoma was not significant. And there was no significant association between cagA expression and gastric carcinoma. (author). 37 refs., 2 tabs., 1 fig.

  2. Purification and relationship with gastric disease of a 130 kDa(CagA) protein of Helicobacter pylorl

    叶少菁; 方平楚; 毛国根; 厉朝龙; 丘翔; 陈海洋


    Objective:The aims of this research were to purify and identify the 130 kDa(CagA) protein of H.pylori clinical isolate HP97002 and evaluate the relationships between the purified 130 kDa(CagA) pro-tein and gastric diseases.Methods:The procedure for isolating the protein included 6 mol/L guanidine ex-tract,size exclusion chromatography and elusion from gel.Sera of 68 patients with gastric diseases(44 with chronic gastritis,15 with atrophic gastritis,7 with peptic ulcer disease,2 with gastric cancer) were obtained,and the serological response to CagA was studied by Westem-blot using the purified protein,Results;The pu-rified protein was 130 kDa and preserved good antigenicity and revealed basic isoelectric point about of 8.1. Among 68 sera,43 sera could recognize the purified protein associated with chronic agastritis 47.7%(21/44),atrophic gastritis 86.7%(13/15),peptic ulcer disease 100%(7/7),gastric cancer 100%(2/2).Compared with each other,the difference was significant(x2=13.327,P=0.004),and 130 kDa(CagA) protein was associated with severe gastric diseases(rs=0.442,P=0.001).Conclusion:The 130 kDa(CagA) protein was associated wih severe gastric diseases.

  3. Helicobacter pylori Infection in Thailand: A Nationwide Study of the CagA Phenotype

    Uchida, Tomohisa; Miftahussurur, Muhammad; Pittayanon, Rapat; Vilaichone, Ratha-korn; Wisedopas, Naruemon; Ratanachu-ek, Thawee; Kishida, Tetsuko; Moriyama, Masatsugu; Yamaoka, Yoshio; Mahachai, Varocha


    Background The risk to develop gastric cancer in Thailand is relatively low among Asian countries. In addition, the age-standardized incidence rate (ASR) of gastric cancer in Thailand varies with geographical distribution; the ASR in the North region is 3.5 times higher than that in the South region. We hypothesized that the prevalence of H. pylori infection and diversity of CagA phenotype contributes to the variety of gastric cancer risk in various regions of Thailand. Methods We conducted a...

  4. Clinical significance of Helicobacter pylori cagA and iceA genotype status

    Nasser; Amjad; Hussain; Ali; Osman; Najibah; Abdul; Razak; Junaini; Kassian; Jeffri; Din; Nasuruddin; bin; Abdullah


    AIM:To study the presence of Helicobacter pylori(H.pylori) virulence factors and clinical outcome in H.pylori infected patients.METHODS:A prospective analysis of ninety nine H.pylori-positive patients who underwent endoscopy in our Endoscopy suite were included in this study.DNA was isolated from antral biopsy samples and the presence of cagA,iceA,and iceA2 genotypes were determined by polymerase chain reaction and a reverse hybridization technique.Screening for H.pylori infection was performed in all patie...

  5. Specific serum immunoglobulin G to Hpylori and CagA in healthy children and adults (south-east of Iran)

    A Jafarzadeh; MT Rezayati; M Nemati


    AIM: To evaluate the serologic IgG response to H pylori and CagA across age groups and in healthy children and adults.METHODS: Totally, 386 children aged 1-15 years and 200 adults aged 20-60 years, were enrolled to study. The serum samples of participant were tested for presence of anti-//pylori and anti-CagA IgG by using ELJSA method.RESULTS: The seroprevalence of H pylori in adults was significantly higher than that observed in children (67.5% vs 46.6%; P < 0.000003). In children, the seropositivity rate in males (51.9%) was significantly (P < 0.05) higher than that observed in females (41.7%). The prevalence of serum anti-CagA antibody was 72.8% and 67.4% in infected children and adults, respectively. The mean titer of serum anti-CagA antibodies was significantly higher among children in comparison to adults (64.1 Uarb/mL vs 30.7; P < 0.03). In infected children and adults the prevalence of serum anti-CagA antibody was higher in males compared to females (78.4% vs 66.3%; P = 0.07 and 75.6% vs 54.71%; P < 0.04, respectively). The age-specific prevalence of anti-H pylori and anti-CagA antibody (in infected subjects) was 37.6% and 59.57% at age 1-5 years, 46.9% and 75% at age 6-10 years, 54.9% and 79.45% at age 11-15, 59.01% and 83.33% at age 20-30 years, 66.6% and 60.52% at age 31-40 years, 73.46% and 63.88% at age 41-50 years and 75.75% and 60% at age 51-60 years with mean titer of anti-CagA antibody of 75.94, 63.32, 57.11, 52.06, 23.62, 21.52 and 21.80 Uarb/mL, respectively. There was significant difference between mean serum anti-CagA antibody in age subgroups (P < 0.001).CONCLUSION: These results showed that anti-//pylori and anti-CagA antibodies were common in the children and adults. The///7y/0//-specific antibodies influenced by age and sex of subjects. Moreover, it seems that males are more susceptible to infection with CagA+ strains compared to females. The seroprevalence of anti-CagA antibody was increased with age, up to 30 years and then decreased. It

  6. Helicobacter pylori CagA Suppresses Apoptosis through Activation of AKT in a Nontransformed Epithelial Cell Model of Glandular Acini Formation

    Vallejo-Flores, Gabriela; Torres, Javier; Sandoval-Montes, Claudia; Arévalo-Romero, Haruki; Meza, Isaura; Camorlinga-Ponce, Margarita; Torres-Morales, Julián; Chávez-Rueda, Adriana Karina; Legorreta-Haquet, María Victoria; Fuentes-Pananá, Ezequiel M.


    H. pylori infection is the most important environmental risk to develop gastric cancer, mainly through its virulence factor CagA. In vitro models of CagA function have demonstrated a phosphoprotein activity targeting multiple cellular signaling pathways, while cagA transgenic mice develop carcinomas of the gastrointestinal tract, supporting oncogenic functions. However, it is still not completely clear how CagA alters cellular processes associated with carcinogenic events. In this study, we evaluated the capacity of H. pylori CagA positive and negative strains to alter nontransformed MCF-10A glandular acini formation. We found that CagA positive strains inhibited lumen formation arguing for an evasion of apoptosis activity of central acini cells. In agreement, CagA positive strains induced a cell survival activity that correlated with phosphorylation of AKT and of proapoptotic proteins BIM and BAD. Anoikis is a specific type of apoptosis characterized by AKT and BIM activation and it is the mechanism responsible for lumen formation of MCF-10A acini in vitro and mammary glands in vivo. Anoikis resistance is also a common mechanism of invading tumor cells. Our data support that CagA positive strains signaling function targets the AKT and BIM signaling pathway and this could contribute to its oncogenic activity through anoikis evasion. PMID:26557697

  7. Relation of Cag-A-positive Helicobacter pylori strain and some inflammatory markers in patients with ischemic heart diseases.

    El-Mashad, Noha; El-Emshaty, Wafaa M; Arfat, Manal S; Koura, Bothina A; Metwally, Shereen S


    Recently, a potential link between infectious agents and athero-sclerosis has been suggested. H. pylori strains bearing the cytotoxin associated gene A (Cag-A) provoked a heightened inflammatory response in vivo and showed stronger relation to gastric complication of this infection. The association between Cag-A positive strain and vascular diseases producing conflicting results. So, the present study aimed to estimate the seroprevalence of H. pylori Cag-A positive strains as a risk factor among different groups of ischemic heart disease and to study its interaction with high sensitivity CRP (hs-CRP) and IL6 as inflammatory host responses. The present study was conducted on anti H. pylori IgG positive 60 ischemic heart disease (IHD) patients and 20 apparently healthy individuals as a control group. IHD patients were classified into 3 groups: (group I) with acute myocardial infarction, unstable angina pectoris patients (group II), chronic stable angina pectoris patients (group III). For all patients and control groups serum anti Cag-A IgG, IL6, hs-CRP, CK, CKMB, LDH, AST and Lipid profile were estimated. IL6 and hs-CRP levels were increased in groups I, II and III as compared with group IV (P < 0.001) with positive correlation between IL6 and hs-CRP in groups I, II and III (P < 0.05). The percentage of anti Cag-A positive cases was similar among the patient groups, but significantly higher than in the control group. Thus, infection with Cag-A positive H. pylori strain may play a role as a risk factor in development of ischemic heart diseases through provocation of high inflammatory response or through other mechanism. Therefore eradication of this infection is important as it is much less expensive than long term treatment of the other risk factors. PMID:20726321

  8. 基因多态性与复发性自然流产的相关性研究%Study on the relationship between gene polymorphism and repeated spontaneous abortion

    李静益; 傅萍


    Repeated spontaneous abortion ( RSA) refers to abortions that occurred in succession two or more than two. The causes of RSA are complicated, including chromosomal abnormality of embryos, abnormal immune functions, luteal insufficiency, infection, genitourinary tract anomaly and so on. But now there are still some etiology and pathogenesis of RSA which are not clear, changes in genetic background and other facters may cause part of populations prone to RSA. Rerrent years some new points are put forward from the perspective of Immunology and Genetics, considering the causes of RSA are related with hereditary. Trying to find out susceptibility gene or pathogenic gene and clarifying the pathogenesis of RSA fundamentally, is important to the RSA treatment and prevention.%复发性自然流产(recurrent spontaneous abortions,RSA)是指连续发生2次或2次以上流产者.RSA的病因复杂,包括胚胎染色体异常、免疫功能异常、黄体功能不足、感染、生殖道异常等.但目前仍有部分RSA患者病因及发病机制尚不清楚,遗传背景等因素的改变可能使部分人群易发生RSA[1].近年来从免疫遗传角度提出了一些新的观点,认为RSA的发生与遗传有关.寻找RSA的易感基因或致病基因,从根本上阐明RSA的发病机理,是RSA治疗和预防的重要途径.

  9. Transgenic Expression of the Helicobacter pylori Virulence Factor CagA Promotes Apoptosis or Tumorigenesis through JNK Activation in Drosophila

    Wandler, Anica M.; Guillemin, Karen


    Author Summary The gastric pathogen Helicobacter pylori infects an estimated 50% of the world's population and is a major risk factor for the development of gastric cancer. Strains of H. pylori that can inject the CagA effector protein into host cells are known to be more virulent, but the potential contributions of host genetics to pathogenesis are not well-understood. Using transgenic Drosophila melanogaster, we show that the genetic context of both the host cells in which CagA is expressed...

  10. Radiosynthesis and biodistribution of [11C]AG957 a potential tyrphostin radiotracer for PET

    Full text: The chemical compound AG957 is an inhibitor of the tyrosine kinase p210bcr-abl, an enzyme which is found exclusively in patients suffering from chronic myeloid leukaemia (CML). We have recently improved our original radio synthesis of AG957 using the PET isotope C-11, thus enabling us to produce larger quantities (60-70 mCi) of the radiotracer. Due to the instability of [11C]AG957 towards oxygen, the formulation had to be stabilised using 0.01 mg/mL of ascorbic acid in 10% ethanol. We are currently evaluating the potential use of this compound as a diagnostic tool for the staging as well as the assessment of response to treatment of CML using PET. So far, studies of the biodistribution of [11C]AG957 in normal and leukaemia bearing mice have been undertaken. Our results have shown that AG957 is metabolised quickly in vivo, most likely forming the respective quinone. This leads to a high reuptake into the bloodstream approximately 20 minutes after injection of the radioligand. As a consequence, poor tumour image quality can be expected due to high levels of blood pool activity. These findings highlight the need to find more stable derivatives of AG957 which retain specificity for the p210bcr-abl receptor. Currently, work is under way to find such compounds and to assess their biological properties. Copyright (2002) The Australian and New Zealand Society of Nuclear Medicine Inc