Analysis of DNA repair gene polymorphisms in glioblastoma

Background

Glioblastoma is the most common and aggressive primary brain tumor in adults. Despite several factors such as ionizing radiation exposure or rare genetic syndromes have been associated with the development of glioblastoma, no underlying cause has been identified for the majority of cases. We thus aimed to investigate the role of DNA repair polymorphisms in modulating glioblastoma risk.

Methods

Genotypic and allelic frequencies of seven common polymorphisms in DNA repair genes involved in nucleotide excision repair (ERCC1 rs11615, ERCC2 rs13181, ERCC6 rs4253079), base excision repair (APEX1 rs1130409, XRCC1 rs25487), double-strand break repair (XRCC3 rs861539) and mismatch repair (MLH1 rs1800734) pathways were analyzed in 115 glioblastoma patients and 200 healthy controls. Haplotype analysis was also performed for ERCC1 rs11615 and ERCC2 rs13181 polymorphisms, located on the same chromosomal region (19q13.32).

Results

Our results indicated that carriers of the ERCC2 Gln/Gln genotype were associated with a lower glioblastoma risk (OR = 0.32, 95% CI 0.12–0.89; P = 0.028), whereas carriers of the MLH1 AA genotype were associated with an increased risk of glioblastoma (OR = 3.14, 95% CI 1.09–9.06; P = 0.034). Furthermore, the haplotype containing the C allele of ERCC2 rs13181 polymorphism and the T allele of ERCC1 rs11615 polymorphism was significantly associated with a protective effect of developing glioblastoma (OR = 0.34, 95% CI 0.16–0.71; P = 0.004).

Conclusions

These results pointed out that MLH1 rs1800734 and ERCC2 rs13181 polymorphisms might constitute glioblastoma susceptibility factors, and also suggested that the chromosomal region 19q could be important in glioblastoma pathogenesis.     

Genetic polymorphisms in the DNA repair gene XRCC1 and susceptibility to glioma in a Han population in northeastern China: A case–control study

Background

Several single nucleotide polymorphisms (SNPs) in the X-ray cross-complementing group 1 (XRCC1) gene have been shown to influence DNA repair and to modify cancer susceptibility. To investigate the role of these loci further, we examined the association of three XRCC1 polymorphisms with the risk of gliomas in a Han population in northeastern China.

Methods

Using a PCR–RFLP method, XRCC1 Arg194Trp, Arg280His and Arg399Gln were genotyped in 624 glioma patients and 580 healthy controls.

Results

Significant differences in the distribution of the Arg399Gln allele were detected between glioma patients and healthy controls by a logistic regression analysis (OR = 1.35, 95%CI 1.17–1.68, P = 0.001). Our data also revealed that the Arg399Gln variant (allele A) carriers had an increased glioma risk compared to the wild-type (allele G) homozygous carriers (OR = 1.40, 95%CI 1.12–1.76, P = 0.003).

Conclusions

These results suggest that the XRCC1 Arg399Gln might influence the risk of developing glioma in a Han population in northeastern Chinese.     

The effect of XPD/ERCC2 Lys751Gln polymorphism on acute leukemia risk: A systematic review and meta-analysis

Aims

Epidemiological studies have assessed the association between xeroderma pigmentosum group D (XPD) Lys751Gln and acute leukemia risk with conflicting results. We performed this meta-analysis to derive a more precise estimation of the relationship. Pooled odds ratio (OR) with 95% confidence interval (95% CI) was used to assess the strength of the association.

Results

Ten published case–control studies including a total of 1494 cases and 2259 controls were identified. Overall, significant risk effects of Lys751Gln genotype was found under the dominant model (OR = 1.16; 95% CI = 1.01–1.34; P = 0.032). When stratified by clinical types, the variant genotype was associated with the acute myeloid leukemia (AML) risk under the heterozygote comparison (OR = 1.20; 95% CI = 1.00–1.43; P = 0.048), the homozygote comparison (OR = 1.35; 95% CI = 1.05–1.74; P = 0.019) and the dominant model (OR = 1.23; 95% CI = 1.04–1.45; P = 0.015), respectively. Furthermore, significantly increased risks were also pronounced in Caucasian AML patients (the homozygote comparison: OR = 1.38; 95% CI = 1.07–1.78; P = 0.013; the dominant model: OR = 1.23; 95% CI = 1.03–1.46; P = 0.020; and the recessive model: OR = 1.26; 95% CI = 1.00–1.60; P = 0.050). No evident heterogeneities were observed for the overall data under all genetic models. In addition, no statistical evidence for publication bias was found using the method of Begg's and Egger's tests.

Conclusion

This meta-analysis suggested that XPD Lys751Gln polymorphism might be a risk factor for AML and Caucasian acute leukemia patients.     

Polymorphisms of the TLR4 gene and risk of gastric cancer

Objective

Toll-like receptor 4 (TLR4) is an important lipo-polysaccharide (LPS) receptor in gastric epithelial cell signaling transduction and plays critical roles in the development and progression of gastric cancer (GC). We investigated the effects of TLR4 gene polymorphisms and gene–environmental interactions on the risk of GC in Northeastern China.

Methods

We genotyped two single-nucleotide polymorphisms (SNPs) in TLR4 (rs10116253 and rs1927911) in 217 GC patients and 294 cancer-free controls using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Odds ratio (OR) and 95% confidence intervals (CIs) were estimated by unconditional logistic-regression models.

Results

Individuals carrying CC genotype of rs10116253 and TT genotype of rs1927911 had a significantly decreased risk of GC (adjusted OR = 0.33, 95% CI 0.18–0.60, P < 0.001 and adjusted OR = 0.37, 95% CI 0.21–0.67, P = 0.001 respectively), compared with TT genotype of rs10116253 and CC genotype of rs1927911. In addition, the SNP effects were additive to the effects of some known environmental factors without any interaction between them in the susceptibility to GC.

Conclusion

Our data suggested that TLR4 gene polymorphisms may be associated with a decreased risk of GC in Chinese population. And these SNPs and their combined effects with environmental factors may be associated with the risk of GC.     

A genetic variant in the promoter of APE1 gene (− 656 T > G) is associated with breast cancer risk and progression in a Chinese population

Background/aims

APE1 is an important DNA repair protein in the base excision repair pathway. Genetic variations in APE1 have been suggested to influence individuals' susceptibility to human malignancies. The present study was aimed to investigate the associations between two functional polymorphisms in APE1 (− 656 T > G and 1349 T>G) and breast cancer risk.

Methods

We genotyped the two polymorphisms in a case-control study of 500 breast cancer patients and 799 age-matched cancer-free controls using the TaqMan method. Unconditional logistic regression adjusted for potential confounding factors was used to assess the associations.

Results

We found that the variant genotypes of the − 656 T>G were significantly associated with decreased breast cancer risk, compared with the wild genotype [TG/GG vs. TT: adjusted odds ratio (OR) = 0.71, 95% confidence interval (CI) = 0.56–0.91], and the protective effect of this polymorphism was more predominant among the subgroups of younger subjects (< 52 years) (OR = 0.65, 95% CI = 0.46–0.92). Besides, we found that the variant genotypes were associated with less frequent lymph node metastasis (P = 0.020, OR = 0.64, 95% CI = 0.44–0.94). We did not observe any significant association between the 1349 T>G polymorphism and breast cancer risk.

Conclusion

Our results suggest that the APE1 − 656 T>G but not the 1349 T>G polymorphism may influence the susceptibility and progression of breast cancer in the Chinese population. Large population-based prospective studies are required to validate these findings.     

The association between Interleukin (IL)-4 gene intron 3 VNTR polymorphism and alopecia areata (AA) in Turkish population

Objective

Alopecia areata (AA) is hypothesized to be an organ-specific autoimmune disease of hair follicles mediated by T cells. As immunological and genetic factors have been implicated in the pathogenesis of AA, the purpose of the present study was to investigate possible associations between the functional Interleukin (IL)-4 gene intron 3 VNTR polymorphism and AA susceptibility and disease progression in Turkish population.

Methods

The study group consisted of 116 unrelated patients with AA and 125 unrelated healthy controls. Genomic DNA was isolated and IL-4 gene 70 bp VNTR polymorphism determined by using polymerase chain reaction (PCR) with specific primers.

Results

No association was observed between AA patients and controls according to genotype distribution (p = 0.051). The allele distribution of IL-4 gene intron 3 VNTR polymorphism was statistically different between AA patients and control group (p = 0.026). The frequency of P1 allele in patients was significantly higher than that in the control group. When the P2P2 genotype was compared with P1P2 + P1P1 genotypes, a statistically significant difference was observed between patients and controls (p = 0.036). Intron 3 VNTR polymorphism in the IL-4 gene was found to be associated with AA susceptibility in Turkish population.

Conclusion

The results suggest that IL-4 VNTR polymorphism in the intron 3 region may be a risk factor for the development of AA among Turkish population. This is the first to report that intron 3 VNTR polymorphism in the IL-4 gene is associated with AA susceptibility.     

Association between interleukin 4 gene intron 3 VNTR polymorphism and recurrent aphthous stomatitis in a cohort of Turkish patients

Objective

Recurrent aphthous stomatitis (RAS) is one of the most common oral mucosal diseases, with a multifactorial etiopathogenesis, an interaction between predisposing factors and/or systemic conditions and immunological components in genetically predisposed subjects. Although there is no clear genetic mode of inheritance, there is evidence that inheritance of specific gene polymorphisms may predispose individuals to RAS. The purpose of the present study was to investigate a possible association between the functional interleukin 4 (IL4) VNTR genetic polymorphism and RAS in a sample of Turkish patients.

Methods

The study included 145 unrelated patients with a clinical diagnosis of RAS and 150 unrelated healthy controls. Genomic DNA was isolated and IL4 gene 70 bp VNTR polymorphism determined by using polymerase chain reaction (PCR) with specific primers.

Results

The distribution of genotype and allele frequencies of IL4 gene intron 3 VNTR polymorphism was statistically different between RAS patients and control group (p < 0.0001 and p < 0.0001, respectively) P2P2 genotype and P2 allele were also found to be protective with a lower risk for susceptibility to RAS (p < 0.0001).

Conclusion

The results of this study suggest that intron 3 VNTR polymorphism in the IL4 gene is associated with RAS susceptibility in Turkish population.     

XRCC3 Thr241Met Polymorphism and Clinical Outcomes of NSCLC Patients Receiving Platinum-Based Chemotherapy: A Systematic Review and Meta-Analysis

Introduction

X-ray repair cross-complementing protein 3 (XRCC3) is an essential gene involved in the double-strand break repair pathway. Published evidence has shown controversial results about the relationship between XRCC3 Thr241Met polymorphism and clinical outcomes of non-small cell lung cancer (NSCLC) patients receiving platinum-based chemotherapy.

Methods

A systematic review and meta-analysis was performed to evaluate the predictive value of XRCC3 Thr241Met polymorphism on clinical outcomes of advanced NSCLC receiving platinum-based chemotherapy. Response to chemotherapy, overall survival (OS) and progression-free survival (PFS) were analyzed.

Results

A number of 11 eligible studies were identified according to the inclusion criteria. Carriers of the variant XRCC3 241Met allele were significantly associated with good response to platinum-based chemotherapy (ThrMet/MetMet vs. ThrThr: OR  = 1.509, 95% CI: 1.099–2.072, P_{heterogeneity}  = 0.618). The XRCC3 Thr241Met polymorphism was not associated with OS (MetMet vs. ThrThr, HR  = 0.939, 95% CI:0.651–1.356, P_{heterogeneity}  = 0.112) or PFS (MetMet vs. ThrThr, HR  = 0.960, 95% CI: 0.539–1.710, P_{heterogeneity}  = 0.198). Additionally, no evidence of publication bias was observed.

Conclusions

This systematic review and meta-analysis shows that carriers of the XRCC3 241Met allele are associated with good response to platinum-based chemotherapy in advanced NSCLC, while the XRCC3 Thr241Met polymorphism is not associated with OS or PFS.     

RASSF1A Ala133Ser polymorphism is associated with increased susceptibility to hepatocellular carcinoma in a Turkish population

Aim

The tumor suppressor gene Ras association domain family 1 isoform A (RASSF1A) regulates cell cycle regulation, apoptosis and microtubule stability and is inactivated by promoter hypermethylation at a high frequency in hepatocellular carcinoma (HCC). A guanine (G)/thymine (T) common single nucleotide polymorphism (SNP) at first position of codon 133 in RASSF1A gene determines an alanine (Ala) to serine (Ser) (Ala133Ser) amino acidic substitution which may alter cancer risk by influencing the function of RASSF1A protein.

Methods

To determine the association of the RASSF1A Ala133Ser polymorphism with the risk of HCC development in a Turkish population, a hospital-based case–control study was designed consisting of 236 subjects with HCC and 236 cancer-free control subjects matched for age, gender, smoking and alcohol status. The genotype frequency of the RASSF1A Ala133Ser polymorphism was determined by using a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay.

Results

Allele and genotype associations of RASSF1A Ala133Ser polymorphism with HCC susceptibility were observed in comparisons between the patient and control samples (P < 0.001). Risk of HCC development in this Turkish population was significantly increased in carriers of the Ser133 variant allele of Ala133Ser polymorphism (Ala/Ser and Ser/Ser genotypes) when compared with homozygote Ala/Ala genotype (OR = 5.47, 95% CI = 3.63–8.25, P = 0.001).

Conclusion

Because our results suggest for the first time that the Ser133 allele of RASSF1A Ala133Ser polymorphism may be a genetic susceptibility factor for HCC in the Turkish population, further independent studies are required to validate our findings in a larger series, as well as in patients of different ethnic origins.     

The impact of GGH -401C > T polymorphism on cisplatin-based chemoradiotherapy response and survival in cervical cancer

Aims

Cervical cancer is the third most frequent cancer in women worldwide, mostly treated with cisplatin-based chemoradiotherapy. Since it is known that folate metabolism might interfere with cisplatin effectiveness, we intended to study the influence of the Gamma Glutamyl Hydrolase -401C > T polymorphism in treatment response in cervical cancer.

Methods

We retrospectively reviewed the clinical data of 167 patients with bulky cervical cancer submitted to cisplatin-based chemoradiotherapy. The genotypes of GGH -401C > T SNP were determined by real-time PCR and statistical analysis was performed by χ² test and survival analysis.

Results

The genotypes of GGH-401C > T were significantly associated with the response to platinum-based chemoradiotherapy. Treatment response was higher in patients carrying the CC genotype, who presented a significant increased chance of treatment response (survival time in months/genotype: 91 for CC Vs 72 for CT/TT; p = 0.035, log rank test). A Cox regression analysis accordingly showed that the presence of the T allele was significantly linked to a worse treatment response (HR = 3.036; CI 95% 1.032-8.934, p = 0.044).

Conclusions

The results of our study suggested the potential interest of GGH -401C > T as a predictive factor of the outcome of cervical carcinoma treated with cisplatin-based chemoradiotherapy.     

A common polymorphism in pre-microRNA-146a is associated with lung cancer risk in a Korean population

Introduction

MicroRNAs (miRs) play important roles in the development and progression of human cancers. MiR-146a down-regulates epidermal growth factor receptor and the nuclear factor-κB regulatory kinase interleukin-1 receptor-associated kinase 1 genes that play important roles in lung carcinogenesis. This study was conducted to evaluate the association between rs2910164C>G, a functional polymorphism in the pre-miR-146a, and lung cancer risk.

Material and methods

The rs2910164C>G genotypes were determined in 1094 patients with lung cancer and 1100 healthy controls who were frequency matched for age and gender.

Results

The rs2910164 CG or GG genotype was associated with a significantly decreased risk for lung cancer compared to that of the CC genotype (adjusted odds ratio = 0.80, 95% confidence interval = 0.66–0.96, P = 0.02). When subjects were stratified according to smoking exposure (never, light and heavy smokers), the effect of the rs2910164C>G genotype on lung cancer risk was significant only in never smokers (adjusted odds ratio = 0.66, 95% confidence interval = 0.45–0.96, P = 0.03, under a dominant model for the C allele) and decreased as smoking exposure level increased (P_trend < 0.001). In line with this result, the level of miR-146a expression in the tumor tissues was significantly higher in the GG genotype than in the CC or CG genotype only in never-smokers (P = 0.02).

Conclusions

These findings suggest that the rs2910164C>G in pre-miR-146a may contribute to genetic susceptibility to lung cancer, and that miR-146a might be involved in lung cancer development.     

Association of ghrelin Leu72Met polymorphism with type 2 diabetes mellitus in Chinese population

Background

Ghrelin, a novel endogenous ligand for the growth hormone secretagogue receptor, is considered to implicate the development of the type 2 diabetes mellitus (T2DM). The Leu72Met (+ 408 C > A) polymorphism of the preproghrelin, has been linked to obesity, insulin resistance and diabetes.

Objective

To investigate the distribution of ghrelin gene Leu72Met polymorphism and its association with the type 2 diabetes mellitus in Chinese population.

Methods

We conducted a case–control study on 877 patients with T2DM and 864 controls, which were genotyped by the polymerase chain reaction (PCR) technique, denaturing high performance liquid chromatography (DHPLC) and DNA sequence analysis. Laboratory analyses were carried out in the hospital laboratory.

Results

No significant difference in the Leu72Met genotype distributions and allele frequency was observed between type 2 diabetes mellitus and controls (both P > 0.05). The polymorphism was not associated with T2DM. However, among the T2DM group, the patients carrying Leu72Leu genotype had significantly increased levels of FPG and serum creatinine compared with variant genotypes (Leu72Met and Met72Met) (P < 0.05). In the control group, the subjects with variant genotypes had significantly increased levels of FINS, HOMA-IR compared with Leu72Leu genotype (P < 0.05).

Conclusion

The Leu72Met polymorphism of the preproghrelin gene was not associated with T2DM in Chinese population. However, it may have some roles in the etiology of insulin resistance.     

Association of the I148M/PNPLA3 variant with elevated alanine transaminase levels in normal-weight and overweight/obese Mexican children

Background and aims

Non-alcoholic fatty liver disease (NAFLD) and elevated alanine transaminase (ALT) levels are common in obese Hispanic adults and children. Recently, a PNPLA3 gene variant (I148M) was strongly associated with NAFLD and higher ALT levels in obese adults, including Hispanics. The aims of this study were to estimate the frequency of elevated ALT levels, and to address the influence of obesity and PNPLA3/I148M on ALT levels in a general population sample of Mexican school-aged children.

Methods

A total of 1037 non-related Mexican children aged 6 to 12 years were genotyped for the I148M variant. Anthropometric, clinical and metabolic parameters were collected from all participants.

Results

Elevated ALT levels (> 35 U/L) were more frequent in obese (26.9%) and overweight (9.3%) than in normal weight children (2.2%). The M148M genotype was significantly associated with elevated ALT levels in this population (OR = 3.7, 95% CI 2.3–5.9; P = 3.7 × 10^− 8), and children carrying the M148M genotype showed significantly lower HDL cholesterol levels and BMI z-core (P = 0.036 and 0.015, respectively). On stratifying by BMI percentile, this genotype conferred a much greater risk of elevated ALT levels in normal weight (OR = 19.9, 95% CI 2.5–157.7; P = 0.005) than overweight and obese children (OR = 3.4, 95% CI 1.3–8.9; P = 0.014 and OR = 3.1, 95% CI 1.7–5.5; P = 1.4 x10^− 4, respectively).

Conclusions

The I148M PNPLA3 variant is strongly associated with elevated ALT levels in normal weight and overweight/obese Mexican children. Thus, the M148M genotype may be considered as an important risk factor for liver damage in this population.     

Association of p53 Arg72Pro polymorphism with bladder cancer: A meta-analysis

Background

p53 tumor suppressor gene Arg72Pro polymorphism has been associated with bladder cancer. However, results were inconsistent. We performed this meta-analysis to estimate the association between p53 Arg72Pro polymorphism and bladder cancer.

Methods

Electronic search of PubMed was conducted to select studies. Studies containing available genotype frequencies of Arg72Pro were chosen, and pooled odds ratio (OR) with 95% confidence interval (CI) was used to assess the association.

Results

The final meta-analysis included 14 published studies with 2176 bladder cancer cases and 2798 controls. The results suggested that the variant genotype was associated with the bladder cancer risk (additive model: OR = 1.72, 95% CI: 1.036–1.325, P = 0.011; dominant model: OR = 1.268, 95% CI: 1.003–1.602, P = 0.047) in Asian subgroup. However, the association was not significant between this polymorphism and bladder cancer risk in Caucasian (additive model: OR = 0.773, 95% CI: 0.564–1.059, P = 0.109; dominant model: OR = 0.685, 95% CI: 0.418–1.124, P = 0.134).

Conclusion

This meta-analysis suggests that p53 Arg72Pro polymorphism is associated with increased risk of bladder cancer in Asians. To validate the association between this polymorphism and bladder cancer, further studies with larger participants worldwide are needed.     

XRCC3 Thr241Met Is Associated with Response to Platinum-Based Chemotherapy but Not Survival in Advanced Non-Small Cell Lung Cancer

Background

A lot of studies have investigated the correlation between x-ray repair cross-complementing group 3 (XRCC3) Thr241Met polymorphism and clinical outcomes in non-small cell cancer (NSCLC), while the conclusion is still conflicting.

Materials and Methods

We conducted this meta-analysis to evaluate the predictive value of XRCC3 Thr241Met polymorphism on response and overall survival of patients with NSCLC. Pooled odds ratios (ORs) and hazard ratios (HRs) and corresponding 95% confidence intervals (95% CIs) were used to estimate the association strength.

Results

A total of 14 eligible studies with 2828 patients were identified according to our inclusion criteria. Meta-analysis results showed that carriers of the variant 241Met allele were significantly associated with good response, compared with those harboring the wild 241Thr allele (Met vs. Thr, OR = 1.453, 95% CI: 1.116–1.892, P_{heterogeneity} = 0.968 and ThrMet+MetMet vs. ThrThr, OR = 1.476, 95% CI: 1.087–2.004, P_{heterogeneity} = 0.696). This significant association was observed in Caucasian population but not in Asian population. On the other hand, there was no significant association of XRCC3 Thr241Met polymorphism with survival (ThrMet+MetMet vs. ThrThr, HR = 1.082, 95% CI: 0.929–1.261, P_{heterogeneity} = 0.564), and there was no difference between Asian and Caucasian population.

Conclusions

These findings suggest a predictive role of XRCC3 Thr241Met polymorphism on response to platinum-based chemotherapy in patients with advanced NSCLC. Additionally, we first report that the XRCC3 Thr241Met polymorphism is associated with response to platinum-based chemotherapy and highlights the prognostic value of the XRCC3 Thr241Met polymorphism.     

Variants of NLRP3 gene are associated with insulin resistance in Chinese Han population with type-2 diabetes

Aims

Nod like receptor pyrin domain containing 3 (NLRP3) is the best characterized member of nod like receptor family. Recent studies suggest that NLRP3 plays a crucial role in the pathogenesis of type-2 diabetes (T2DM), and variants in NLRP3 affect its mRNA stability and expression. Therefore, we hypothesize that the variants in NLRP3 gene may contribute to T2DM susceptibility. The aim of this study is to evaluate the association of NLRP3 SNPs with T2DM in Chinese Han patients.

Methods

Two common variants in NLRP3 gene, rs10754558 and rs4612666, were detected using the polymerase chain reaction–restriction fragment length polymorphism procedure in 952 unrelated T2DM patients and 871 healthy controls. All participants were unrelated Chinese Hans.

Results

The GG genotype and G allele frequencies of rs10754558 were significantly higher in T2DM patients than those in controls (for GG genotype, 19.6% vs. 14.5%, p = 0.019; for G allele, 43.9% vs. 39.8%, p = 0.013). The GG genotype of rs10754558 was significantly associated with higher LDL-C levels and more prone to insulin resistance, as evaluated by HOMA-IR or QUICK indexes.

Conclusions

The variant (rs10754558) in NLRP3 is related to insulin resistance and increased risk of T2DM in Chinese Han population.     

Variations in genotype–phenotype correlations in phenylalanine hydroxylase deficiency in Chinese Han population

Background

The value of genotyping to predict variant phenotypes in patients with phenylalanine hydroxylase (Pah) deficiency is a matter of debate. However, there exists no comprehensive population relationship study focused on the Han Chinese.

Methods

We analyzed genotype–phenotype correlation for 186 different genotypes in 338 unrelated Chinese patients harboring 109 different Pah mutations. Two systems were used in this process. The first was a phenotype prediction system based on arbitrary values (AV) attributed to each mutation. The second was a pair-wise correlation analysis. The observed phenotype for AV analysis was the corresponding metabolic phenotype stratified according to the pretreatment phenylalanine (Phe) value.

Results

We found that the observed phenotype matched the predicted phenotype in 54.41% of 272 patients for whom AV information was available; the highest degree of concordance (61.83%) was found in patients with null/null genotypes, whereas the lowest “concordance rate” (32.69%) was observed for patients with expected mild-PKU phenotype. There are repeated inconsistencies for such mutations as R241C, R243Q, R261Q, V388M, V399V, R408Q, A434D and EX6-96A>G which are associated with variable phenotypes in patients with identical genotype. Significant correlations were disclosed between pretreatment Phe values and predicted residual activity (r = − 0.45643, P < 0.0001) or AV sum (r = − 0.59523, P < 0.0001).

Conclusion

Our study supports the notion that the Pah mutation genotype is the main determinant of metabolic phenotype in most patients in a particular population, and provided novel insights into the values that underpin the subsequent treatment and the prognosis of PKU in Chinese.     

The contribution of platelet glycoproteins (GPIa C807T and GPIba C-5T) and cyclooxygenase 2 (COX-2G-765C) polymorphisms to platelet response in patients treated with aspirin

Objective

Aspirin is an antiplatelet agent commonly used in treatment of patients with high risk to develop stroke and myocardial infarction. However, inter-individual variability regarding the inhibition of platelet function by aspirin is well documented. In this study, the correlation between platelet glycoproteins (GPIa C807T and GPIba C-5T) and cyclooxygenase 2 (COX-2G-765C) polymorphisms and antiplatelet response in patients treated with aspirin was investigated.

Methods

Jordanian adult patients (n = 584) who are taking aspirin as an antiplatelet agent participated in the study. Platelet aggregation response was measured using Multiplate Analyzer® system. Polymerase chain reaction–restriction fragment length polymorphism assay (PCR–RFLP) was used for genotyping of the examined polymorphisms.

Results

Aspirin resistance was found in 15.8% of patients. Response to aspirin was significantly associated with GPIba C-5T polymorphism (P < 0.05). However, the GPIa C807T and COX-2G-765C polymorphisms were not related to aspirin resistance (P > 0.05).

Conclusion

A considerable fraction of the Jordanian population is resistant to the antiplatelet effect of aspirin, which might be related to GPIba C-5T polymorphism.     

The polymorphism − 1131T > C in apolipoprotein A5 gene is associated with dyslipidemia in Brazilian subjects

Background

Polymorphisms in apolipoprotein A5 gene (APOA5) have been associated with higher triglyceride levels in many populations. The aim of the study was to determine the allelic and genotypic distribution of the APOA5 − 1131T > C polymorphism and to identify the association of the genetic variant and the risk for dyslipidemia.

Methods

We genotyped 109 dyslipidemic subjects and 107 controls. The total cholesterol, triglycerides and HDL-c were determined enzymatically. Comparison of means among groups was calculated by ANOVA. Significant differences among groups were evaluated by Student–Newman–Keuls test.

Results

The minor allele C was more frequent in dyslipidemic subjects than controls (p = 0.019) and confers an increased individual risk for dyslipidemia (OR = 1.726, CI 95% = 1.095–2.721). The genotype analysis by gender showed that this allele was more frequent in dyslipidemic males (p = 0.037; OR = 2.050, CI 95% = 1.042–4.023). When participants were analyzed according to genotypes TT and TC/CC, C-carriers presented higher cholesterol and triglycerides levels than TT homozygous (p = 0.046 and 0.049, respectively).

Conclusions

The allele C confers higher total cholesterol and triglycerides levels in dyslipidemic adults. The APOA5 − 1131T > C polymorphism is associated with dyslipidemia in male subjects.     

Klotho gene polymorphism of rs3752472 is associated with the risk of urinary calculi in the population of Han nationality in Eastern China

Background/aims

The incidence of urolithiasis has considerably increased throughout the world in the last two decades. Clinical researches have showed an association between oxidative stress and stone formation. Emerging evidence indicated a novel function for klotho protein in anti-oxidative stress. In this study, we aimed at investigating a possible relationship between klotho gene polymorphisms and the risk of calcium oxalate urolithiasis in the population of Han nationality in Eastern China.

Methods

Klotho gene polymorphisms rs3752472 in exon3, rs650439 in intron 4 and rs577912 in intron 1 were investigated in 426 patients with calcium oxalate stones compared with 282 age-matched healthy volunteers with no history of stone formation, using TaqMan SNP Genotyping Assays.

Results

Significant differences were found between rs3752472 and the risk of nephrolithiasis as CC genotype of rs3752472 klotho polymorphism had almost 2-fold increased stone risk compared with the heterozygote genotype CT and homozygous genotype TT(95% CI = 1.013–2.255, OR = 1.512,p = 0.043).

Conclusion

Our results showed that the rs3752472 polymorphism of klotho gene is associated with the risk of calcium oxalate urolithiasis and may act as a risk factor during stone formation in our study population.