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1.
The present study investigated the role of Xeroderma pigmentosum group A (XPA) polymorphism (A23G and G709A) with lung cancer risk and its association with overall survival in North Indians. 370 cases and 370 controls were investigated to evaluate association between XPA polymorphism (A23G and G709A) with lung cancer risk using logistic regression analysis. A follow-up study was also conducted for 291 lung cancer cases illustrating correlation between overall survival in lung cancer patients and XPA variants. GG genotype showed an increased lung cancer risk (p = 0.0007) for A23G polymorphism whereas G709A polymorphism was associated with significant protective effect in heterozygous (AG) subjects (p = 0.001). When stratified according to smoking status an increased risk for lung cancer was observed for GG genotype in A23G polymorphism (p = 0.0002). A poor survival in females carrying variant genotype (GG) was observed (p = 0.001; MST = 4.16 months) for A23G polymorphism. Adenocarcinoma patients with heterozygous genotype showed an increased hazard ratio (p = 0.02) for A23G polymorphism. G709A was associated with a reduced hazard ratio marking a better survival among mutant females (HR 0.17; p = 0.05; MST = 18.63 months). It can be concluded that A23G polymorphism might contribute to increased lung cancer risk in North Indian population emphasizing on poor survival among females. G709A polymorphism might result in protective effect in lung cancer subjects. The present study had a low sample size but it could act as reference for the large sample studies in future.  相似文献   

2.
So far, epidemiological studies have been performed to investigate the association of CDKN2A/B rs4977756 polymorphism and glioma risk. However, the results from different studies remain inconsistent. To clarify these conflicts and to quantitatively evaluate the effect of rs4977756 polymorphism on glioma risk, a meta-analysis was conducted using relevant published clinical studies about rs4977756 polymorphisms and glioma risk. Relevant studies concerning the association between rs4977756 polymorphism and risk of glioma were included in this meta-analysis. Odds ratio (OR) and 95 % confidence interval (CI) were calculated under fixed or random effects models when appropriate. Subgroup analyses were performed by race. This meta-analysis included 13 studies with a total of 8129 cases and 15,858 controls. The pooled results showed that there was an obvious association of CDKN2A/B rs4977756 polymorphism with risk of glioma in all four comparison models (dominant model/AG + GG vs. AA: OR = 1.36, 95 %CI = 1.20–1.54, p < 0.01; heterozygote comparison/AG vs. AA: OR = 1.31, 95 %CI = 1.12–1.53, p < 0.01; homozygote comparison/GG versus AA: OR = 1.49, 95 %CI = 1.36–1.64, p < 0.01; additive model/G vs. A: OR = 1.23, 95 %CI = 1.18–1.28, p < 0.01, respectively). For the subgroup analyses of ethnicities, similar results were observed in Caucasians. However, the association was not found between rs4977756 polymorphism and the risk of glioma in all models for the Asian studies. The CDKN2A/B rs4977756 polymorphism is obvious increase the risk of glioma in Caucasians. Future studies are needed to confirm the results in other ethnic populations.  相似文献   

3.
Either the role of the adaptive immune system or the interaction between innate and adaptive immune systems in familial Mediterranean fever (FMF) is not clear so far. So, we planned to search for the interaction between the innate and adaptive immune systems in the pathogenesis of FMF by investigating polymorphism for CTLA-4 gene, which plays a role in controlling antigen presentation to T cells. We also aimed to investigate whether there is an association between ?318C/T and +49A/G polymorphisms in the CTLA-4 gene and the main clinical features of the disease. 75 FMF patients and 179 controls were studied. Polymorphism was detected by the PCR-RFLP technique. The CT genotype and T allele frequencies of the ?318C/T polymorphism and the haplotype frequency for the ?318T/+49A in the CTLA-4 gene were higher in the FMF (21.3, 21.3, and 10.7 %) when compared with the controls (10.6, 10.6, and 5.3 %; P = 0.029, 0.044, and 0.029). However, these differences did not reach a statistically significant level after the Bonferroni correction. A significant linkage disequilibrium was found between the ?318C/T and +49A/G polymorphisms in the CTLA-4 gene (D′ = 0.997, r2 = 0.027, P = 0.0002). Genotype and carrier frequencies of the CTLA-4 gene +49A/G polymorphism were not significantly different between FMF patients and healthy controls. No association was found between the studied polymorphisms and the main clinical features of the disease. Our findings suggest that although not statistically significant, higher frequencies of CTLA-4 gene ?318CT genotype, T allele, and ?318T/+49A haplotype in FMF patients may be related to the non-autoimmune pathogenesis of FMF.  相似文献   

4.
Gastric cancer incidence varies considerably among populations, even those with comparable rates of Helicobacter pylori infection. To test the hypothesis that genetic variation plays a role in gastric disease, we assessed the relationship between genotypes and gastric histopathology in a Colombian study population, using a genotyping array of immune-related single nucleotide polymorphisms (SNPs). Two synonymous SNPs (rs6061243 and rs6587239) were associated with progression of premalignant gastric lesions in a dominant-effects model after correction for multiple comparisons (p = 2.63E?07 and p = 7.97E?07, respectively); effect sizes were β = ?0.863 and β = ?0.815, respectively, where β is an estimate of effect on histopathology scores, which ranged from 1 (normal) to 5 (dysplasia). In our replication cohort, a second Colombian population, both SNPs were associated with histopathology when additively modeled (β = ?0.256, 95 % CI = ?0.47, ?0.039; and β = ?0.239, 95 % CI = ?0.45, ?0.024), and rs6587239 was significantly associated in a dominant-effects model (β = ?0.330, 95 % CI = ?0.66, 0.00). Because promoter methylation of GATA5 has previously been associated with gastric cancer, we also tested for the association of methylation status with more advanced histopathology scores in our samples and found a significant relationship (p = 0.001). A multivariate regression model revealed that the effects of both the promoter methylation and the exonic SNPs in GATA5 were independent. A SNP-by-methylation interaction term was also significant. This interaction between GATA5 variants and GATA5 promoter methylation indicates that the association of either factor with gastric disease progression is modified by the other.  相似文献   

5.
Epidemiological genetics established that heritability in determining the risk of myocardial infarction (MI) is substantially greater when MI occurs early in life. However, the genetic architecture of early-onset and late-onset MI was not compared. We analyzed genotype frequencies of SNPs in/near 20 genes whose protein products are involved in the pathogenesis of atherosclerosis in two groups of Russian patients with MI: the first group included patients with age of first MI onset <60 years (N?=?230) and the second group with onset ≥60 years (N?=?174). The control group of corresponding ethnicity consisted of 193 unrelated volunteers without cardiovascular diseases (93 individuals were over 60 years). We found that in the group of patients with age of onset <60 years, SNPs FGB rs1800788*T, TGFB1 rs1982073*T/T, ENOS rs2070744*C and CRP rs1130864*T/T were associated with risk of MI, whereas in patients with age of onset ≥60 years, only TGFB1 rs1982073*T/T was associated with risk of MI. Using APSampler software, we found composite markers associated with MI only in patients with early onset: FGB rs1800788*T?+?TGFB1 rs1982073*T; FGB rs1800788*T?+?LPL rs328*C?+?IL4 rs2243250*C; FGB rs1800788*T?+?ENOS rs2070744*C (Fisher p values of 1.4?×?10?6 to 2.2?×?10?5; the permutation p values of 1.1?×?10?5 to 3.0?×?10?4; ORs?=?2.67–2.54). Alleles included in the combinations were associated with MI less significantly and with lower ORs than the combinations themselves. The result showed a substantially greater contribution of the genetic component in the development of MI if it occurs early in life, and demonstrated the usefulness of genetic testing for young people.  相似文献   

6.
Odonata have been widely used as indicators for the biomonitoring of terrestrial and aquatic habitats due to their sensitivity to environmental impacts. We aimed to determine whether the larval or adult phases of these insects were the best predictors of variation in habitat parameters and the loss of environmental integrity. Specimens were collected during three seasons (dry, rainy, and ebb) from 12 points in the Suiá-missu River basin, at the headwaters of the Xingu River in Mato Grosso, Brazil. The Protest analysis indicated a high degree of congruence between the assemblages of larvae and adults in streams with varying degrees of habitat integrity (R = 0.832, p < 0.001, m 2 = 0.307). When the congruence with environmental factors was analyzed, a significant association was found only for the larval phase (R = 0.318, p = 0.03, m 2 = 0.888). When the suborders were analyzed separately, congruence was confirmed for anisopteran adults (R = 0.338, p = 0.031, m 2 = 0.885) and larvae (R = 0.417, p = 0.003, m 2 = 0.826) and for the zygopteran adults (R = 0.345, p = 0.027, m 2 = 0.881) and larvae (R = 0.405, p = 0.011, m 2 = 0.836). These results indicate that both larvae and adults respond systematically to environmental impacts. We suggest that either life phase can be used for biomonitoring, given their effectiveness for the interpretation of disturbance in terrestrial and aquatic habitats. These findings further reinforce the effectiveness of this insect order for the detection of modifications to the environment, showing that they are good indicators of environmental conditions.  相似文献   

7.
Previous studies have indicated that the cognitive impairment or deficit is associated with GABAergic signaling in central nervous system. Inspired by the finding that receptor GABRR2 modulates concentration of GABA and phasic inhibitory GABAergic transmission in brain. This study investigated to what extent a genetic variant (c.1423C>T, rs282129) of GABRR2 gene modulates individuals’ general cognitive ability in 987 Chinese Han people. Results showed a significant influence of GABRR2 gene polymorphism on individuals’ Raven’s Standard Progressive Matrices (RSPM) performance (F = 3.58, P = .028 by ANOVA and χ 2 = 9.35, P = .009 by K–W test, respectively), even if non-genetic factors were partialed out (gender, major, types of birthplace, and socioeconomic index) (B = ?.67, SE = .26, t = 2.63, P = .009). The finding provided a strong evidence, to our knowledge, for the view that genetic variant of GABRR2 gene may contribute to the difference of individuals’ general cognitive ability, independently.  相似文献   

8.
Apolipoprotein A5 (APOA5 or APO A-V) polymorphisms have long been reported to be associated with cardiovascular disease and plasma lipid levels. The present study was undertaken to investigate the relationship between the rs662799, rs3135507, and rs2075291 with biochemical parameters in the Turkish Cypriot population. A total of 100 Turkish Cypriot volunteer subjects (53 female and 47 male), with a mean age of 40.8, participated in the study. A basic biochemical analysis, including serum glucose, total serum cholesterol, HDL-C, LDL-C, and triglycerides, was performed for each participant. Genotyping for the APOA5 three polymorphisms was performed by polymerase chain reaction followed by restriction fragment length polymorphism analysis. Biochemical parameters except the low-density lipoprotein cholesterol (LDL-C) were all within the normal limits. LDL-C was found to be slightly elevated in participants according to WHO guidelines. With respect to the genotype and allele distributions of APOA5 rs662799 T>C polymorphism, TT genotypes are more frequent (62%) in the population and the frequency of T allele is 0.78. The TT genotype for APOA5 rs2075291 G<T was not observed in the study population. Ancestral GG is the only genotype present in the study population. Minor Allele Frequency of APOA5 rs3135507 G>A variant is 0.12 for the A allele. No association between the two studied APOA5 polymorphisms (rs662799 and rs3135507) and the biochemical components of glucose, total cholesterol, and triglyceride were observed. On the other hand, a strong statistical association between the high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) clinical parameters and APOA5 rs662799 CC and rs3135507 AA genotypes was found (p = 0.014 and p = 0.017, respectively). APOA5 polymorphisms rs662799 and rs3135507, with the CC and the AA genotypes, respectively, are associated with increased levels of both high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) in the Turkish Cypriot population.  相似文献   

9.
Gene–environment interactions have long been known to play an important role in complex disease aetiology, such as nasal polyposis (NP). The present study supports the concept that DNA repair gene polymorphisms play critical roles in modifying individual susceptibility to environmental diseases. In fact, we investigated the role of polymorphisms in DNA repair genes and cadmium as risk factors for Tunisian patients with NP. To the best of our knowledge, this is the first report on the impact of combined effects of cadmium and ERCC3 7122 A>G (rs4150407), ERCC2 Lys751Gln (rs13181) and XRCC1 Arg399Gln (rs25487) genes in the susceptibility to NP disease. Significant associations between the risk of developing NP disease and ERCC2 [odds ratio (OR)?=?2.0, 95 % confidence interval (CI)?=?1.1–3.7, p?=?0.023] and ERCC3 (OR?=?2.2, 95 % CI?=?1.2–4.1, p?=?0.013) genotypes polymorphisms were observed. Blood concentrations of Cd in NP patients (2.2 μg/L) were significantly higher than those of controls (0.5 μg/L). A significant interaction between ERCC3 (7122 A>G) polymorphism and blood-Cd levels (for the median of blood-Cd levels: OR?=?3.8, 95 % CI?=?1.3–10.8, p?=?0.014 and for the 75th percentiles of blood-Cd levels: OR?=?2.7, 95 % CI?=?1.1–7.2, p?=?0.041) was found in association with the risk of NP disease. In addition, when we stratified ERCC2, ERCC3 and XRCC1 polymorphism genotypes by the median and 75th percentiles of blood-Cd levels, we found also significant interactions between ERCC2 (Lys751Gln) and ERCC3 (7122 A>G) genotypes polymorphism and this metal in association with NP disease. However, no interaction was found between XRCC1 (Arg399Gln) polymorphism genotypes and Cd in association with NP disease.  相似文献   

10.
This study investigated the genetic association of three single nucleotide polymorphisms(SNPs; rs10483727, rs33912345, and rs146737847) at the SIX1-SIX6 locus with primary open angle glaucoma(POAG) in the Chinese population. A total of 866 subjects with POAG(685 high-tension glaucoma(HTG) and 181 normal-tension glaucoma(NTG)) and 266 control individuals were included. Significant genetic association was identified for rs10483727 in HTG(P=0.02; odds ratio(OR)=1.31), NTG(P=7.41×10~(-6); OR=2.71), and POAG(i.e., HTG and NTG combined; P=0.001; OR=1.44). rs33912345 was also significantly associated with HTG(P=0.008; OR=1.36), NTG(P=2.72×10~(-6); OR=2.27), and POAG(P=3.84×10~(-4); OR=1.49). The rare SIX6 mutation, rs146737847, was not found in the subjects enrolled in this study. Stratification by patient age identified that both rs10483727 and rs33912345 were significantly associated with NTG in patients aged above 40 years(P=2.08×10~(-5); OR=2.28), whereas in patients aged between 20–40 years, rs33912345 was significantly associated with NTG(P=0.017; OR=2.06). In HTG, the genetic associations for both rs10483727 and rs33912345 were significant in patients aged between 20–40 years(P=0.006; OR=1.56) but not in those aged above 40 years(P=0.118, OR=1.21 and P=0.042, OR=1.29, respectively). This study replicated the association of POAG with two SNPs at the SIX1-SIX6 locus and demonstrated that SNPs, rs10483727 and rs33912345, are significantly associated with POAG, especially with NTG in patients aged above 40 years.  相似文献   

11.
Apolipoprotein C3 (ApoC3) plays a regulatory role in triglyceride (TG) metabolism. The higher level of TG can be a cause in pathogenesis of the vascular diseases or metabolic syndrome (MetS). In this study, we examined the associations of ApoC3 polymorphisms (?482C>T rs2854117 and 3238G>C rs5128) with Korean MetS patients. A total of 835 subjects were investigated, including 320 patients with MetS and 515 healthy subjects. The genotype analysis of the ApoC3 polymorphisms was performed by polymerase chain reaction-restriction fragment length polymorphism methods. Of the two polymorphisms studied, we observed a significant difference in the ?482C>T polymorphism between the MetS and control groups. The TT genotype of the ?482C>T polymorphism was associated with increased risk for MetS, compared with the controls (OR 1.627, 95 % CI 1.075–2.463, P = 0.021). The association was female-specific. No associations were found for the risk of MetS in the 3238G>C polymorphism. Haplotypes composed of two polymorphisms, however, were associated with MetS susceptibility in only male group. The 3238G>C polymorphism was significantly associated with TG levels (P = 0.013). Our data suggest that the ApoC3 ?482C>T polymorphism is associated with increased MetS susceptibility in the Korean population.  相似文献   

12.
NKG2C is an activating receptor that is preferentially expressed on natural killer (NK) cells. The gene encoding NKG2C (killer cell lectin-like receptor C2, KLRC2) is present at different copy numbers in the genomes of different individuals. Deletion at the NKG2C locus was investigated in a case–control study of 1522 individuals indigenous to East- and West-Africa and the association with the ocular Chlamydia trachomatis infection and its sequelae was explored. The frequency of homozygous KLRC2 deletion was 13.7 % in Gambians and 4.7 % in Tanzanians. A significantly higher frequency of the deletion allele was found in West-Africans from the Gambia and Guinea-Bissau (36.2 % p = 2.105 × 10?8, 26.8 % p = 0.050; respectively) in comparison to East-African Tanzanians where the frequency of the deletion is comparable to other human populations (20.9 %). We found no evidence for an association between the numbers of KLRC2 gene copies and the clinical manifestations of trachoma (follicular trachoma or conjunctival scarring). A new method for imputation of KLRC2 genotypes from single nucleotide polymorphism (SNP) data in 2621 individuals from the Gambia further confirmed these results. Our data suggest that NKG2C does not play a major role in trachomatous disease. We found that the deletion allele is present at different frequencies in different populations but the reason behind these differences is currently not understood. The new method offers the potential to use SNP arrays from genome wide association studies to study the frequency of KLRC2 deletion in other populations and its association with other diseases.  相似文献   

13.
14.
Interferon gamma (IFN-γ) is a multifunctional cytokine that plays an important role in modulating almost all phases of the immune response and may be responsible for the increased valvular fibrosis and calcification in the pathogenesis of rheumatic heart disease (RHD). The aim of this study was to investigate the possible relationship between the IFN-γ +874 T/A polymorphism and the severity of valvular damage in the Turkish population. The IFN-γ genotypes were determined in 152 RHD patients and 151 healthy controls by ARMS-PCR. Differences in genotype distribution between patients with RHD and control were evaluated by the χ2 test. All statistical analyses were performed with SPSS 15.0 Software program. Frequency of the AA genotype was found to be significantly lower and the TT genotype significantly higher in the RHD group compared to controls (p = 0.002 and p = 0.018, respectively). The TT genotype was found to be significantly higher (26.8% vs. 9.1%, p = 0.009) and the AA genotype significantly lower (29.1% vs. 8.2%, p = 0.001) in the severe valvular disease (SVD) group compared to mild valvular disease group. In the SVD group, 79 patients had mitral balloon valvotomy and/or mitral valve replacement and had significantly higher TT genotype compared to patients with medical follow-up (30.4% vs. 19%, p = 0.001). The data demonstrated that TT genotype is associated with both RHD and the severity of RHD.  相似文献   

15.
The objective of this study was to determine the occurrence and distribution of antibiotic resistant (AR) lactic acid bacteria (LAB) in Indian poultry. LAB from poultry farm feces (n = 21) and samples from slaughter houses comprising chicken intestine (n = 46), raw meat (n = 23), and sanitary water (n = 4) were evaluated and compared with those from organic chicken (OC) collected from nearby villages. Screening studies showed 5–7 log units higher erythromycin (ER), tetracycline (TC) and vancomycin (VAN) resistant LAB from conventional poultry chicken (CC) compared to OC. Molecular characterization of isolated cultures (n = 32) with repetitive-PCR profiling and 16S rRNA gene sequencing revealed their taxonomical status as Enterococcus faecium (n = 16), Enterococcus durans (n = 2), Lactobacillus plantarum (n = 10), Lactobacillus pentosus (n = 1) and Lactobacillus salivarius (n = 3). The isolates were found to harbor erm(B), msr(C), msr(A/B), tet(M), tet(L) and tet(K) genes associated with Tn916 and Tn917 family transposons. Expression studies through real-time PCR revealed antibiotic-induced expression of the identified AR genes. In vitro and in vivo conjugational studies revealed transfer of ER and TC resistant (ERR and TCR) genes with transfer frequencies of 10?7 and 10?4 transconjugants recipient?1, respectively. Although no known VAN resistance (VANR) genes were detected, high phenotypic resistance was observed and was transferable to the recipient. From a public health point of view, this study reports Indian poultry as a major source of high levels of AR bacteria contaminating the food chain and the environment. Thus, urgent and determined strategies are needed to control the spread of multiple AR bacteria.  相似文献   

16.
In this study, fungemia cases from four tertiary hospitals located in Shanghai and Anhui province in China from March 2012 to December 2013 were enrolled to investigate clinical features, species distribution, antifungal susceptibility and strain relatedness. During the study period, 137 non-duplicate cases and their corresponding isolates were collected. Six different genera of fungi were identified, of which Candida spp. were the most common (126/137, 91.97 %), with C. albicans predominating (48/137, 35.03 %). The non-Candida fungi rate reached 8.03 % (11/137), and Pichia spp. was the most common (5/137, 3.65 %). Compared with C. albicans, non-C. albicans fungi-associated fungemia was more likely in younger (p = 0.004) and male patients (χ 2 = 6.2618, p = 0.0123) and patients from ICUs (χ 2 = 6.3783, p = 0.0116). Overall, the susceptible/WT rates of common Candida spp. to fluconazole, itraconazole, voriconazole, flucytosine, amphotericin B and caspofungin were 74.63, 92.31, 93.16, 96.58, 100 and 95.69 %, respectively. C. tropicalis and C. guilliermondii had a low susceptibility to fluconazole: 79.95 and 77.78 %, respectively. No isolates were resistant/WT to caspofungin, but C. parapsilosis and C. guilliermondii had high MIC90 values; 1 and 2 mg/L, respectively. In terms of genotyping, MLST was taken for C. glabrata and C. tropicalis, while microsatellite marker analysis was used for C. albicans and C. parapsilosis. C. glabrata was predominantly clone ST7, accounting for 75 %, while the other isolates showed genetic diversity. Considering the increased proportion of non-C. albicans fungi and the presence of endemic clones of C. glabrata, it is essential to undertake additional surveillance of fungemia.  相似文献   

17.
Recently, subfraction analysis of serum low density lipoprotein (LDL) is considered to be a better predictor of the risk of coronary heart disease (CHD) compared to the other lipid parameters. The aim of this study was to examine the effects of the HDL-associated Taq1B (rs708272) SNP of cholesterol ester transfer protein (CETP) gene on serum LDL subfractions in patients with CHD. Serum lipid levels were measured enzymatically and LDL subfraction analysis was carried out by the Lipoprint System (Quantimetrix, CA, USA). The CETP rs708272 SNP was studied in 66 healthy controls and 79 patients with CHD receiving statin therapy by the PCR–RFLP technique. The CHD patients had elevated antiatherogenic LDL-1 subfraction (p = 0.042), decreased atherogenic IDL-C subfraction (p = 0.023), and total IDL (p = 0.030) levels compared to the healthy controls. The CETP rs708272 Taq1B minor B2 allele was associated with increased levels of antiatherogenic LDL-1 (B2: 0.40 ± 0.20 vs. B1B1: 0.25 ± 0.08, p = 0.004) and large-LDL (LDL 1–2) subfractions in the CHD group (B2 allele: 0.68 ± 0.41 vs. B1B1: 0.42 ± 0.20; p < 0.05), while it was associated with reduced levels of the large-LDL subfraction in healthy subjects (B2 allele: 0.29 ± 0.14 vs. B1B1: 0.54 ± 0.24; p = 0.017). However, there was no statistically significant association between the CETP rs708272 SNP and small dense LDL subfraction (LDL 3–7) and lipoprotein levels (p > 0.05). Our findings have indicated that the CETP rs708272 SNP together with statin therapy may show a favorable effect on antiatherogenic LDL-1 and large-LDL subfractions in CHD patients with an atherogenic effect on large-LDL subfraction in healthy subjects. Based on these results, it can be concluded that the effects of the CETP variation on LDL subfraction could change in cardiometabolic events such as CHD and statin therapy.  相似文献   

18.
Estimation of variability and genetic relationships among breeding materials is one of the important strategies in crop improvement programs. Morphological (plant height, spike length, a number of florets/spike), physiological (chlorophyll content, chlorophyll fluorescence, and rapid light curve parameters) and Directed amplification of minisatellite DNA (DAMD) markers were used to investigate the relationships among 50 Gladiolus cultivars. Cluster analysis based on morphological data, physiological characteristics, molecular markers, and cumulative data discriminated all cultivars into seven, five, seven, and six clusters in the unweighted pair-group method using arithmetic mean (UPGMA) dendrogram, respectively. The results of the principal coordinate analysis (PCoA) also supported UPGMA clustering. Variations among the Gladiolus cultivars at phenotypic level could be due to the changes in physiology, environmental conditions, and genetic variability. DAMD analysis using 10 primers produced 120 polymorphic bands with 80% polymorphism showing polymorphic information content (PIC = 0.28), Marker index (MI = 3.37), Nei’s gene diversity (h = 0.267), and Shannon’s information index (I = 0.407). Plant height showed a positive significant correlation with Spike length and Number of florets/spike (r = 0.729, p < 0.001 and r = 0.448, p = 0.001 respectively). Whereas, Spike length showed positive significant correlation with Number of florets/spike (r = 0.688, p < 0.001) and Chlorophyll content showed positive significant correlation with Electron transport rate (r = 0.863, p < 0.001). Based on significant morphological variations, high physiological performance, high genetic variability, and genetic distances between cultivars, we have been able to identify diverse cultivars of Gladiolus that could be the potential source as breeding material for further genetic improvement in this ornamental crop.  相似文献   

19.
This study investigates associations between G/A polymorphism of the epithelial PAS domain protein 1 (EPAS1) gene (rs1867785) and the maximum rate of oxygen consumption (VO2max) in male Russian athletes. The study engaged 241 male athletes from different sports; the control group of nonathletes included 92 subjects. Increased frequencies of the AA and AG genotypes of the EPAS1 gene (χ2 = 14.16, p = 0.03) were found in the cohort of male athletes. The frequencies of these alleles in the subgroups with moderate (EPAS1*A 38.1% and EPAS1*G 61.9%) and high (EPAS1*A 41.8% and EPAS1*G 58.2%) VO2max values significantly differed from those in the control group (χ2 = 7.53, p = 0.006 and χ2 = 6.58, p = 0.01, respectively). The higher aerobic capacities are probably associated with the presence of at least one minor A allele of the EPAS1 gene in the genome.  相似文献   

20.

Key message

This article provides significant data in the debate on whether siltation might have a negative impact on the hydraulic functioning of two widespread mangrove tree species Avicennia marina and Rhizophora mucronata.

Abstract

Elevated sediment addition, or siltation, within mangrove ecosystems is considered as being negative for trees and saplings, resulting in stress and higher mortality rates. However, little is known about how siltation influences the hydraulic functioning of mangrove trees. Comparing two mangrove tree species (Avicennia marina Vierh. Forsk. and Rhizophora mucronata Lam.) from low and high-siltation plots led to the detection of anatomical and morphological differences and tendencies. Adaptations to high siltation were found to be either mutual among both species, e.g., significant smaller single leaf area (p A.marina  = 0.058, F1.38 = 3.8; p R.mucronata  = 0.005, F1.38 = 8.7; n = 20 × 20) and a tendency towards smaller stomatal areas (p A.marina  = 0.131, F1.8 = 2.8; p R.mucronata  = 0.185, F1.8 = 2.1, n = 5 × 60), or species-specific trends for A. marina, such as higher phloem band/growth layer ratios (p = 0.101, F1.8 = 3.4, n = 5 × 3) and stomatal density (p = 0.052, F1.8 = 5.2, n = 5 × 4). All adaptations seemingly contributed to a comparable hydraulic conductivity independent of the degree of siltation. These findings indicate that silted trees level off fluctuations in their hydraulic performance as a survival mechanism to cope with this less favourable environment. Most of the trees’ structural adaptations to cope with siltation are similar to known drought stress-imposed adaptations.
  相似文献   

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