Polymorphism of folate metabolism genes and thrombotic complications in patients with functionally single ventricle

Aim. To analyze the relationships between the carriage of polymorphic variants in the folate metabolism genes and the development of thrombotic complications in patients with single ventricle (SV) during surgical treatment.Material and Methods. A total of 102 children with SV were examined in the performed research. All patients underwent surgical hemodynamic correction of congenital heart disease (CHD). According to a retrospective chart review, thrombosis was diagnosed in 12.7 % of the examined patients with SV. The analysis of polymorphism in the MTR A2756G enzyme gene revealed significant differences between the groups of patients with a history of thrombosis and without it.Results. We found that the risk of developing thrombosis was associated with the carriage of homozygous genotype 2756AA of the MTR enzyme gene (OR = 11.21; 95% CI: 1.39–89.96; p = 0.023).

VDR Polymorphisms in Autoimmune Connective Tissue Diseases: Focus on Italian Population

Vitamin D is an important hormone involved in various physiologic processes, and its activity is linked to binding with vitamin D receptor (VDR). Genetic polymorphisms in the VDR gene could modulate the expression or function of the receptor and, consequently, alter the effects of vitamin D. Variants in VDR gene have been associated with susceptibility to many illnesses sensitive to vitamin D administration and to autoimmune disorders, but no data are available regarding autoimmune connective tissue diseases in Italian population. We analyzed three VDR polymorphisms in 695 Italian patients with autoimmune connective tissue diseases (308 with systemic lupus erythematosus (SLE), 195 with primary Sjogren’s syndrome (pSS), and 192 with rheumatoid arthritis (RA)) and in 246 healthy controls with the aim to evaluate a possible association of VDR SNPs with susceptibility to these diseases in the Italian population. Genotyping of rs2228570, rs7975232, and rs731236 in VDR gene was performed by an allelic discrimination assay. A case/control association study and a genotype/phenotype correlation analysis have been performed. We observed a higher risk to develop SLE for rs2228570 TT genotype ( P = 0.029 , OR = 1.79 ). No association was observed between susceptibility to pSS or RA and this SNP, although this variant is significantly less present in RA patients producing autoantibodies. For rs7975232 SNP, we observed a significant association of the variant homozygous genotype with SLE ( P = 0.009 , OR = 1.82 ), pSS ( P = 0.046 , OR = 1.66 ), and RA ( P = 0.028 , OR = 1.75 ) susceptibility. Moreover, we reported associations of this genotype with clinical phenotypes of SLE and pSS. Lastly, the GG genotype of rs731236 was associated with a lower RA susceptibility ( P = 0.045 , OR = 0.55 ). Our results show that the explored VDR polymorphisms are significantly associated with autoimmune connective tissue disorders and support the hypothesis that the genetic variability of VDR gene may be involved in susceptibility to these diseases in Italian population.

MTHFR and MDR1 Gene Polymorphisms in Yakut Patients with Non-Syndromic Orofacial Clefts

The aim of our study was to investigate the relationship between the MDR1 and MTHFR gene polymorphisms and non-syndromic cleft lip with or without cleft palate (NSCL/P) in the Yakut population in the Republic of Sakha (Yakutia). Methods and Results: The sample of examined persons consisted of 60 children with NSCL/P. The NSCL/P group was divided into the CLP (cleft lip with cleft palate) subgroup (n=31), CLO (cleft lip only) subgroup (n=14), and CPO (cleft palate only) subgroup (n=15). The comparison group (control) included 174 healthy volunteers who did not have relatives with OFCs. The study of the MDR1 rs1045642 SNP and the MTHFR rs1801133 SNP was performed by PCR and RFLP analysis. Analysis of the frequency distribution of alleles and genotypes depending on the severity of clefts showed that the carriage of the TT homozygous genotype of the MDR1 rs1045642 SNP was associated with significant risk for the development of NSCL/P (OR=2.52, 95% CI: 1.19-5.32, P=0.02). Analysis of the recessive model (TT vs CC + TC) also found a significant risk of NSCL/P with the TT genotype carriage (OR=2.20, 95% CI: 1.06-4.57, P=0.04). Analysis of the over-dominant model (TC vs TT + CC) showed that the heterozygous TC genotype had a protective effect (OR=0.41; 95% CI: 0.22-0.77, P=0.01) on the development of NSCL/P. Subgroup analysis according to NSCL/P subtypes (CLO, CPO and CLP) showed that the MDR1 rs1045642 SNP was significantly associated with a high risk of CPO in three genetic models: heterozygous [(TT vs TC): OR=5.03; 95% CI: 1.55-16.32; P=0.01], recessive [(TT vs CC + TC): OR=3.96; 95% CI: 1.32-11.95; P=0.02], and over-dominant [(TC vs TT + CC): OR=0.23; 95% CI: 0.08-0.66; P=0.01]. Conclusion: A study of two SNPs in the MDR1and MTHFR genes revealed a statistically significant increased risk for NSCL/P in carriers of the TT genotype of the MDR1 rs1045642 SNP.

Association of the IRF6 rs2235371 and rs861019 Polymorphisms with Non-Syndromic Cleft Lip with or without Cleft Palate in the Yakut Population

Background: Non-syndromic cleft lip with or without cleft palate (NSCL/P) is one of the most common birth defects. NSCL/P can be broadly divided into cleft lip only (CLO), cleft palate only (CPO), and cleft lip with cleft palate (CLP) based on clinical presentation. The aim of this study was to investigate the relationship between the IRF6 gene polymorphisms and non-syndromic cleft lip with or without cleft palate (NSCL/P) in the Yakut population. Methods and Results: In 23 OFC patients and 58 unrelated control subjects from the Yakut population, we tested two SNPs (rs2235371 and rs861019) with a minor allele frequency of more than 5% in the candidate gene IRF6. We found that the SNP marker rs861019 showed significant differences in allele frequencies (OR=2.07, 95%CI: 1.01–4.23, P=0.04) between the NSCL/P patients and the comparison group. Analysis of allele frequencies for rs861019 SNP in subgroups showed that there was a difference in the frequency between CLP and control (OR=5, 95% CI: 1.61-15.53, P=0.11); however, this result was not significant. Genotype analysis showed significant differences in patients from the CLP subgroup in comparison with controls for homozygous (AA compared with GG) (OR=9.00, 95% CI: 1.03–78.58, P=0.03), heterozygous (GA compared with GG) (OR=5.50, 95% CI: 1.05-28.75, P=0.04,), recessive (GG compared with GA + AA) (OR=6.67, 95% CI: 1.61-27.58; RR=4.78, 95% CI: 1.42–16.10, P=0.008,) and co-dominant (GG compared with GA, compared with AA) (P=0.02) inheritance models. Diplotype analysis showed that the NSCL/P group was more likely to have the [CC]-[GG] diplotype than the comparison group. This diplotype carries the risk GG genotype (rs861019) (30.4%) and does not carry the risk T allele(rs2235371). In the CLP subgroup, two diplotypes ([CT]-[GG] and [CC]-[GG]) were found more often than in the comparison group. Both diplotypes carry the risk GG genotype(rs861019; 33.3%). In the CPO subgroup, the [CT]-[GG] diplotype was more common. In the CLO subgroup, only two diplotypes ([CC]-[GA] and [CC]-[GG]) were found, both of which were more common than in the comparison group (75% and 25%).. It is likely that these results for the CLO and CPO subgroups were influenced by the small size of both samples. Unlike the NSCL/P and CLP groups, in these samples, diplotypes with the homozygous genotype GG (rs861019) without the homozygous genotype TT (rs2235371) were more common. Diplotypes with a homozygous genotype of the TT risk allele were not found in the studied groups except for the comparison group, where the [TT]-[AA] diplotype was represented by a low frequency (0.17%). Conclusion: The present study provides strong statistical support (for the first time to our knowledge) that genetic variants of the IRF6 rs861019 SNP are associated with NSCL/P in Yakuts.

All You Need to Know About UGT1A1 Genetic Testing for Patients Treated With Irinotecan: A Practitioner-Friendly Guide

Irinotecan is an anticancer agent widely used for the treatment of solid tumors, including colorectal and pancreatic cancers. Severe neutropenia and diarrhea are common dose-limiting toxicities of irinotecan-based therapy, and UGT1A1 polymorphisms are one of the major risk factors of these toxicities. In 2005, the US Food and Drug Administration revised the drug label to indicate that patients with UGT1A1*28 homozygous genotype should receive a decreased dose of irinotecan. However, UGT1A1*28 testing is not routinely used in the clinic, and specific reasons include lack of access to concise information on this wide issue as well as mixed recommendations by regulatory and professional entities. To assist oncologists in assessing whether and when to use UGT1A1 genetic testing in patients receiving irinotecan-based therapies, this article provided (1) essential knowledge of UGT1A1 polymorphisms; (2) an update on the impact of UGT1A1 polymorphisms on efficacy and toxicity of contemporary irinotecan-based regimens; (3) dosing adjustments based upon the UGT1A1 genotypes, and (4) recommendations from currently available guidelines from the US and international scientific consortia and major oncology societies.

Effect of vascular endothelial growth factor gene polymorphisms on disease activity in rheumatoid arthritis

Background The full etiology of RA remains unclear; in addition to the contributions of infectious, hormonal, and environmental factors, several lines of evidence have suggested that the disease has a genetic basis. The VEGF gene is also an independent risk factor for RA severity and correlates with multiple disease parameters, such as disease activity, joint damage, and functional disability. This case-control study aimed to investigate the impact of a common genetic polymorphism in the vascular endothelial growth factor (VEGF) gene on disease activity and synovial lesions in patients with rheumatoid arthritis (RA). Results T allele was present in the RA group more frequently (22.5% vs. 10% respectively in controls). The C allele was less frequent in the RA group (77.7% vs. 90% respectively in controls) (P = 0.002). Homozygous genotype (CC) was found in 61.2% of patients and 82.5% of controls, homozygous genotype (TT) in 6.3% of patients, and 2.5% of controls while heterozygous (CT) genotype in 32.5% of patients and 15% of controls (P = 0.011). Grade 1 PDUS was found in 30.6% of CC and 11.5% of CT and not found in TT genotypes. The grade 2 was found in 69.4%, 65.4%, and only 20% of CC, CT, and TT genotypes, respectively. The grade 3 was found in 80% of TT, 23.1% of CT, and none of CC genotypes (P < 0.001). Conclusion An association between VEGF gene SNP rs3025039 and increased risk for RA among a sample of Egyptian population was noticed. VEGF gene polymorphism appears to be a potential diagnostic activity indicator and a promising therapeutic target for RA patients.

Polymorphism rs2682818 participates in the progression of colorectal carcinoma via miR-618-TIMP1 regulatory axis

Colorectal carcinoma (CRC) has a high morbidity and mortality. Current studies have confirmed a variety of microRNA polymorphisms were associated with tumor susceptibility, however, the mechanisms are still unknown. In this study, we were aimed to clarify how polymorphism rs2682818 participated in the progression of CRC. First of all, the differential expression of miR-618 was assessed by quantitative real-time polymerase chain reaction in CRC patients with different genotypes of polymorphism rs2682818, including homozygous (TT) genotype, homozygous (GG) genotype and heterozygous (TG) genotype. Secondly, plasmids carried miR-168 precursor sequences harboring rs2682818 (SNP type) or without rs2682818 (wild type) were transfected into 293T cells to verify that polymorphism rs2682818 affected miR-618 expression. Thirdly, CCK-8 assay, flow cytometry assay, transwell assay and mouse xenograft assay were performed to measure the biological functions of miR-618 in CRC. Fourthly, the candidate target genes of miR-618 which were predicted by bioinformatics tools were verified by luciferase reporter assay. Finally, in order to explain the potential molecular mechanisms, western blotting was performed to demonstrate the differential expression and phosphorylation of pathway related proteins. The results showed that miR-618 was down-regulated in colon cancer, especially in CRC patients with rs2682818 GG homozygous genotype. Higher expression of mature miR-618 occurred in patients with TT homozygous genotype, and these patients usually had a longer survival time. Moreover, miR-618 mimic obviously impaired the growth and invasion ability of CRC cells, and miR-618 mimic also remarkably promoted CRC cell apoptosis. Our luciferase experiments confirmed that TIMP1 was a target of miR-618 in CRC cells. Knockdown of TIMP1 also significantly inhibited the malignant cytological features of CRC, including malignant growth and invasion as well as apoptosis resistance. In summary, polymorphism rs2682818 participated in the progression of CRC via affecting the expression of mature miR-618 in CRC cells, and miR-618 inhibited the progression of CRC via targeting TIMP1expression.

PAX7 gene polymorphism in muscular temporomandibular disorders as potentially related to muscle stem cells

Background Temporomandibular disorders (TMD) are a group of painful and debilitating disorders, involving the masticatory muscles and/or the temporomandibular joint (TMJ). Chronic TMD pain can be associated with genetic changes in the key muscle development genes. Objective To evaluate the association between polymorphisms in the PAX7 (paired box 7) gene and masticatory myalgia in patients with temporomandibular disorders (TMD). Materials and methods This is a case-control study. Patients with TMD were divided into two groups: (a) presence of muscular TMD (n = 122) and (b) absence of muscular TMD (n = 49). Genomic DNA was obtained from saliva samples from all participants to allow for genotyping single nucleotide polymorphisms in PAX7 (rs766325 and rs6659735). Over-representation of alleles was tested using chi-square or Fisher’s exact tests. Values of p < 0.05 were considered to be statistically significant. Results Individuals without muscular TMD were less likely to have the PAX7 rs6659735 GG genotype (p = 0.03). No associations were found for PAX7 rs766325. Conclusions Alterations in PAX7 may influence muscular pathophysiology and individuals with TMD and the rs6659735 homozygous genotype (GG) are seemingly associated with muscular involvement of the disorder. No associations were found in the region rs766325.

Polymorphisms of the KCNS1, COMT and OPRM1 genes and development of postoperative pain in patients with osteoarthritis who underwent total knee or hip replacement

Postoperative pain (POP) is a serious complication that reduces the result of total knee (TKA) or hip arthroplasty (THA) in patients with osteoarthritis (OA). The search for predictors of postoperative pain is an actual problem.The aim of the study – to assessing relationship the polymorphisms of the KCNS1, COMT and OPRM1 genes and the development of POP in OA patients who underwent TKA or THA.Material and methods. The study group consisted of 95 patients with OA knee or hip (64.6% of women, 65.4±9.0 years) who underwent TKA (47.8%) or THA (52.2%). The presence of POP was determined when pain in the area of surgical intervention ≥40 mm (100 mm visual analog scale, VAS) persisted or appeared 3 and 6 months after surgery. All patients underwent genotyping of polymorphisms of the genes KCNS1 (rs734784), COMT (rs6269, rs4633) and OPRM1 (rs1799971) by polymerase chain reaction in real time using original sequence-specific primers and samples labeled with various fluorescent labels. Registration and interpretation of the obtained results were carried out on the DT-96 amplifier (DNA-Technology LLC, Russia).Results. POP was observed in 32.6% of patients who underwent TKA or THA. The frequency of POP after TKA and THA was 30.2% and 34.0% (p=0.882). Statistical analysis revealed no differences in the frequencies of the genotypes of the studied genes (p>0,05). The presence of a homozygous genotype of the GG polymorphism of the KCNS1 gene (rs734784) was associated with the presence of POP in accordance with the recessive genetic model (GG vs AA+AG; odds ratio (OR) – 3.96 [95% confidence interval (CI): 1.51; 10.37]; p=0.005). The presence of the mutant allele T (TT+CT) in the genotype of the COMT polymorphism (rs4633) reduced the risk of POP compared to the carrier of the CC genotype (OR=0.32 [95% CI: 0.12; 0.83]; p=0.02) in accordance with the dominant genetic model. There was no significant correlation between the development of POP and the carrier of different genotypes and alleles of the COMT (rs6269) and OPRM1 (rs1799971) genes.Conclusions. There is a statistically significant association the polymorphism of the KCNS1 (rs734784) and COMT (rs4633) genes and the development of chronic POP in patients who underwent TKA or THA. Further studies of the genetic predisposition to POP are required on more clinical material.

A Personalized Approach to the Treatment of Primary Open-Angle Glaucoma

Aim — to study of gene polymorphisms affecting the effectiveness of timolol treatment of primary open-angle glaucoma.Patients and Methods. The study included 39 Russian patients (29 women and 10 men) aged 53 to 89 years old with a diagnosis of primary open-angle glaucoma (POAG). Intraocular pressure (IOP) was measured before the start of therapy and after 2 weeks during treatment. Сoefficient of decrease in IOP was calculated in percentage of its initial level (∆D). Patients were genotyped according to the polymorphic loci MMP1-160insG, MMP12A-82G, TIMP1C536T, ADRB1Arg389Gly, ADRB1Ser49Gly, NAT2Lys268Arg, GSTP1Ile105Val using the corresponding SNP-express reagent kits (NPF Lytech, Moscow).Results. No effect of MMP12A-82G, TIMP1C536T, ADRB1Arg389Gly, NAT2Lys268Arg polymorphisms on efficiency of reduction of IOP under action of thymolol in “best” eyes was revealed. The carriage of a homozygous genotype GSTP1Ile105Ile resulted in the best ophthalmic hypotensive effect of a timolol (∆D ≥ 20 %), which probability was 5.63 times higher in comparison with ∆D < 20 %. In the “worst” eyes, the association of carriage of a combination of wild genotypes GSTP1Ile105Ile×NAT2Lys268Lys with the best response of patients to timolol was revealed. The ophthalmic hypotensive effect of 10 ≤ ∆D < 20 % in such carriers was more than 11 times more likely than ∆D < 10 %.Conclusion. The carriage of the wild genotype GSTP1Ile105Ile determines the best ophthalmic hypotensive effect of timolol and can be a prognostic marker for the effective treatment of patients with POAG. The combination of wild genotypes GSTP1Ile105Ile×NAT2Lys268Lys can contribute to the better therapeutic effect of timolol, and mutant ones can prevent it.