B2 Allele Research Articles

CYP3A4*1B but Not CYP3A5*3 as Determinant of Long-Term Tacrolimus Dose Requirements in Spanish Solid Organ Transplant Patients.

Tacrolimus (TAC) is a commonly used immunosuppressive drug in solid organ transplantation. Pharmacogenetics has been demonstrated before to be decisive in TAC pharmacotherapy. The CYP3A5*3 variant has been reported to be the main determinant of TAC dose requirements; however, other polymorphisms have also proven to be influential, especially in CYP3A5 non-expressor patients. The aim of this study is to evaluate the influence of genetic polymorphisms in TAC therapy in a cohort of Spanish transplant recipients. Genetic analysis including ten polymorphic variants was performed, and demographic and clinical data and pharmacotherapy of 26 patients were analyzed. No significant differences were found in weight-adjusted dose between CYP3A5 expressors and non-expressors (0.047 mg/kg vs. 0.044 mg/kg), while they were found for carriers of the CYP3A4*1B allele (0.101 mg/kg; p < 0.05). The results showed that patients with at least one CYP3A4*1B allele had a higher TAC dose and lower blood concentration. Dose-adjusted TAC blood levels were also lower in CYP3A4*1B carriers compared to non-carriers (0.72 ng/mL/mg vs. 2.88 ng/mL/mg). These results support the independence of CYP3A5*3 and CYP3A4*1B variants as determinants of dose requirements despite the linkage disequilibrium present between the two. The variability in genotype frequency between ethnicities may be responsible for the discrepancy found between studies.

Determination of NAT2 Genotypes in a Cohort of Patients with Suspected TB in the State of Rio de Janeiro.

The human N-acetyltransferase 2 enzyme, encoded by the NAT2 gene, plays an important role in the metabolism of isoniazid, the main drug used to treat tuberculosis. The interindividual variation in the response of patients to drug treatment for tuberculosis may be responsible for the occurrence of unfavorable outcomes. The presence of polymorphisms in genes associated with the metabolism and transport of drugs, receptors, and therapeutic targets has been identified as a major determinant of this variability. The objective of this study was to identify the genetic profile of NAT2 in the study population. Using the obtained genomic DNA followed by PCR amplification and sequencing, the frequency of nine SNPs as well as alleles associated with slow (47.9%), intermediate (38.7%), and fast acetylation phenotypes (11.3%), in addition to those whose phenotype has not yet been characterized (2.1%), was estimated. The NAT2*5B allele was identified more frequently (31.3%). The description of SNPs in pharmacogenes and the establishment of their relationship with the pharmacokinetics of an individual offer an individualized approach that allows us to reduce the unfavorable outcomes of a therapy, ensure better adherence to treatment, prevent the emergence of MDR strains, reduce the cost of treatment, and improve the quality of patients' lives.

Association of HLA-DQ4/5 genotype polymorphisms with celiac disease in a group of children in Southwest Iran: A case-control study.

Celiac disease (CD) has proinflammatory and pathogenic immune responses to gluten in intestinal tissue, leading to structural changes in the mucosa of the small intestine. The association of human leukocyte antigen (HLA)-DQ2 and DQ8 genotypes with CD has been previously reported. This test has a negative predictive value close to 100%, so its main purpose is to rule out the detection of CD completely or almost completely. There is limited information regarding HLA-DQ4/5 in CD. This study was conducted to determine the HLA-DQ4/5 genotypes in a group of Southwestern Iranian children with CD. We conducted a case-control study in Southwest Iran involving 100 participants, employing a nonprobabilistic sampling method. Samples were taken from participants' oral buccal mucosa at Imam Sajjad Hospital of Yasuj, Iran. Then DNA was extracted from these samples and used to determine the frequency of HLA-DQ4/5 genotypes through Sequence-Specific Primer-Polymerase Chain Reaction assay. SPSS 20 was utilized for statistical analyses. Fifty diagnosed patients with CD (high anti-tissue transglutaminase [tTG]-IgA level [upper limit of normal] with pathological findings of Marsh III) and 50 non-CD individuals (normal anti-tTG-IgA level and normal total IgA level) were enrolled in the study from August 5, 2022 to October 15, 2023. Findings showed that the DQ4a*4b allele has the highest frequency in the CD samples (78%, p < 0.01) followed by the DQ5a*5b allele (12%, p < 0.01). Additionally, there was a higher prevalence of DQ4/DQ5 in patients with CD compared to controls (odds ratio = 6.5, confidence interval = 0.84 to 69.46, p < 0.01). Furthermore, a significant association was found among HLA DQ4/5 genotype, age (>9.5) (p < 0.01), and gender (female) (p < 0.05). The observed significant differences among HLA-DQ4 and HLA-DQ5 in Iranian CD samples against controls and the high value of the relative risks showed the significant function of the studied alleles in the prevalence of CD in Iranian patients.

The possible protective role of HLA B27 and relevant immune markers in Juvenile Idiopathic Arthritis patients.

JIA is a disease with different immunological characteristics and a complicated genetic foundation. HLA B27 is a risk factor for the development of JIA, and its impact on immunopathogenesis of the disease is also an area of interest. To determine whether HLA B27 and immune markers varied between JIA patients and healthy population. This comparative cross-sectional study was conducted at Immunology Department of University of Health sciences (UHS), Lahore from February 2018 till August 2021. A total of (71) JIA patients and (34) healthy controls were enrolled. B cells were enumerated by flowcytometry, ELISA was used for serum cytokines estimation and HLA B27 allele was detected by SPSS polymerase chain reaction. The HLA B27 allele was significantly more in the control group than in the patient group, suggesting it is a protective allele to prevent JIA. Peripheral blood B cell counts and percentages were significantly lower in the HLA B27 positive group than in the HLA B27 negative group of control population. Serum cytokine levels were not significantly different between the HLA B27 positive and HLA B27 negative allele of the two study populations. In this study B cells are different between the two groups of control population however; serum cytokines are comparable between the study groups. Though, it was indicated that HLA B27 may be a preventive allele in the onset of JIA.

The pharmacogenetics of tacrolimus in renal transplant patients: association with tremors, new-onset diabetes and other clinical events.

Our study is the first study to investigate the effect of SNPs in CYP3A5, CYP3A4, ABCB1 and POR genes on the incidence of tremors, nephrotoxicity, and diabetes mellitus. A total of 223 renal transplant patients receiving tacrolimus and mycophenolate mofetil (MMF) were recruited. Both adults and children patients participated in the study. Genotyping was performed using PROFLEX-PCR followed by RFLP. MPA and tacrolimus plasma concentrations were measured by immunoassay. The AUC0-12h of MMF was estimated by a Bayesian method. We found a statistically significant association between the CYP3A5*3 and CYP3A4*1B genotypes and the tacrolimus exposure. We found a lower occurrence of nephrotoxicity (p = 0.03), tremor (p = 0.01), and new-onset diabetes (p = 0.002) associated with CYP3A5*1 allele. The CYP3A4*1B allele was significantly associated with a lower occurrence of new-onset diabetes (p = 0.026). The CYP3A5*1 allele was significantly associated with an increased risk of acute and chronic rejection (p = 0.03 and p < 0.001, respectively). Our results support the usefulness of tacrolimus pharmacokinetics in pre-kidney transplant assessments.

Fifty years after the discovery of the association of HLA B27 with ankylosing spondylitis

The human lymphocyte antigen B27 (HLA B27) is a member of the HLA class I family of genes in the major histocompatibility complex whose name goes back to its discovery...

Effect of NAM-1 genes on the protein content in grain and productivity indices in common wheat lines with foreign genetic material introgressions in the conditions of Belarus.

Modern varieties of common wheat (Triticum aestivum L.) bred mainly for high productivity are often of low grain quality. The identification of NAM-1 alleles associated with high grain protein content in wheat relatives has enhanced the significance of distant hybridization for the nutritional value of T. aestivum L. grain. In this work we aimed to study the allelic polymorphism of the NAM-A1 and NAM-B1 genes in wheat introgression lines and their parental forms and evaluate the effects of various NAM-1 variants on the grain protein content and productivity traits in the field conditions of Belarus. We studied parental varieties of spring common wheat, the accessions of tetraploid and hexaploid species of the genus Triticum and 22 introgression lines obtained using them (2017-2021 vegetation periods). Full-length NAM-A1 nucleotide sequences of T. dicoccoides k-5199, T. dicoccum k-45926, T. kiharae, and T. spelta k-1731 accessions were established and registered with the international molecular database GenBank. Six combinations of NAM-A1/B1 alleles were identified in the accessions studied and their frequency of occurrence varied from 40 to 3 %. The cumulative contribution of NAM-A1 and NAM-B1 genes to the variability of economically important wheat traits ranged from 8-10 % (grain weight per plant and thousand kernel weight) to up to 72 % (grain protein content). For most of the traits studied, the proportion of variability determined by weather conditions was small (1.57-18.48 %). It was shown that, regardless of weather conditions, the presence of a functional NAM-B1 allele ensures a high level of grain protein content; at the same time, it does not significantly decrease thousand kernel weight. The genotypes combining the NAM- A1d haplotype and a functional NAM-B1 allele demonstrated high levels of productivity and grain protein content. The results obtained demonstrate the effective introgression of a functional NAM-В1 allele of related species increasing the nutritional value of common wheat.

N-acetyltransferase 2 genetic polymorphism modifies genotoxic and oxidative damage from new psychoactive substances.

The use of new psychoactive substances (NPS) as drugs of abuse is common and increasingly popular, particularly among youth and neglected communities. Recent studies have reported acute toxic effects from these chemicals; however, their long-term toxicity is unknown. Genetic differences between individuals likely affect the toxicity risk. Arylamine N-acetyltransferase 2 (NAT2) capacity differs among individuals due to genetic inheritance. The goal of the present study is to investigate the gene-environment interaction between NAT2 polymorphism and toxicity after exposure to these chemicals. We measured N-acetylation by human NAT1 and NAT2 and found that N-acetylation of NPS is carried out exclusively by NAT2. Differences in N-acetylation between NAT2*4 (reference allele) and NAT2*5B (common variant allele) were highly significant (p < 0.0001). Using DNA repair-deficient genetically engineered Chinese hamster ovary (CHO cells), expressing human CYP1A2 and either NAT2*4 or NAT2*5B, we measured the induction of DNA double-strand breaks ([Formula: see text]H2Ax) following treatment of the CHO cells with increasing concentrations of NPS. The induction of [Formula: see text]H2Ax showed a NAT2 allele-dependent response, higher in the NAT2*4 vs NAT2*5B alleles (p < 0.05). Induction of oxidative stress (ROS/RNS) was evaluated; we observed NAT2 allele-dependent response for all compounds in concentrations as low as 10 [Formula: see text]M, where NAT2*4 showed increased ROS/RNS vs NAT2*5B (p < 0.05). In summary, NPS are N-acetylated by NAT2 at rates higher in cells expressing NAT2*4 than NAT2*5B. Exposure to psychoactive chemicals results in genotoxic and oxidative damage that is modified by the NAT2 genetic polymorphism.

Intrinsic Folding Properties of the HLA-B27 Heavy Chain Revealed by Single Chain Trimer Versions of Peptide-Loaded Class I Major Histocompatibility Complex Molecules.

Peptide-loaded Major Histocompatibility Complex (pMHC) class I molecules can be expressed in a single chain trimeric (SCT) format, composed of a specific peptide fused to the light chain beta-2 microglobulin (β2m) and MHC class I heavy chain (HC) by flexible linker peptides. pMHC SCTs have been used as effective molecular tools to investigate cellular immunity and represent a promising vaccine platform technology, due to their intracellular folding and assembly which is apparently independent of host cell folding pathways and chaperones. However, certain MHC class I HC molecules, such as the Human Leukocyte Antigen B27 (HLA-B27) allele, present a challenge due to their tendency to form HC aggregates. We constructed a series of single chain trimeric molecules to determine the behaviour of the HLA-B27 HC in a scenario that usually allows for efficient MHC class I molecule folding. When stably expressed, a pMHC SCT incorporating HLA-B27 HC formed chaperone-bound homodimers within the endoplasmic reticulum (ER). A series of HLA-B27 SCT substitution mutations revealed that the F pocket and antigen binding groove regions of the HLA-B27 HC defined the folding and dimerisation of the single chain complex, independently of the peptide sequence. Furthermore, pMHC SCTs can demonstrate variability in their association with the intracellular antigen processing machinery.

Association of CYP2A6 Genetic Polymorphism and Lung Cancer in Female Never Smokers

Background: The major significant factor that affected lung cancer development among female passive smokers is environmental tobacco smoke. Nicotine can be found in a never smoker population, such as a child whose father is a smoker. Lung carcinogenesis in never smoker populations is affected by nicotine metabolism by CYP2A6 gene, which encodes the main nicotine metabolizing-enzyme. The aim of this study was to assess the genetic polymorphism of CYP2A6 and its association with secondhand smokers among females who have suffered from lung cancer in North Sumatra population.Materials and methods: This study was a case-control study, composed of 53 case subjects and 46 control subjects that were involved through a purposive sampling technique from two hospitals in Medan. PCR-RFLP was used for the examination of CYP2A6 gene to determine the genotype. The data were analyzed with conditional logistic regression test using Epi Info 7.0 software.Results: The most common genotype of CYP2A6 detected in this study was *1B/*1B (40.4%), while *1B allele had the highest prevalence (55.5%). There was no significant association between CYP2A6 genotype (p-value=0.61) or alleles (p-value=0.25) and the incidence of lung cancer.Conclusion: There was no association between CYP2A6 polymorphism and the incidence of lung cancer in secondhand smoker females.Keywords: CYP2A6, PCR-RFLP, female secondhand smokers, lung cancer

Influence of N‐acetyltransferase polymorphism in the N‐acetylation of asparagine and putrescine

Amino acids play central roles in cancer progression beyond their function as building blocks for protein synthesis. Because of this, targeting amino acid acquisition and uptake has been proved to be a potential therapeutic strategy to limit cancer cell growth while leaving the normal tissues largely intact. Polyamines like Putrescine (Put) are low molecular weight, aliphatic polycations found in the cells of all living organisms. Recent findings have described that abundance of N‐acetylated Asparagine (Asp) and Put are highly correlated with N‐acetylation capacity of N‐acetyltransferase 1 (NAT1). Here we tested the N‐acetylation of Asp and Put by recombinant human NAT1 and NAT2 as well as the effect of N‐acetylation polymorphisms in the metabolism of these substrates. Using genetically engineered CHO cells expressing either NAT1*4, NAT1*14, NAT2*4 or NAT2*5B alleles, in vitro N‐acetylation activity reactions were quantified using HPLC. Our results show that Asp is metabolized by both NAT1 and NAT2; enzymatic activity was quantified at different time points up to 60 min, as well as, increasing concentrations of the cofactor AcCoA. Using 100 μM of AcCoA, the formation of N‐acetyl Asp was 1.7 ±0.32 nmoles Ac‐Asp/mg protein in the reference allele (NAT1*4); on the other hand, NAT1*14 (slow) allele produced 1.12 ±0.32 nmoles Ac‐Asp/mg protein (p&lt; 0.01); increasing AcCoA to 300 μM resulted in an increase 3.98 ±0.58 and 2.93 ±0.62 nmoles Ac‐Asp/mg protein, respectively (p&lt; 0.01), Finally, Increasing the availability of AcCoA to 1 mM, produced an N‐acetylation rate of 9.82 ±3.73 and 4.64 ±0.61 nmoles Ac‐Asp/mg protein (p&lt; 0.001). For NAT2, in the presence of 100 μM of AcCoA, the reference allele (NAT2*4) produced 1.43 ±0.6, whereas NAT2*5B (slow) produced 1.05 ±0.19 nmoles Ac‐Asp/mg protein (p&lt; 0.05). 300 μM of AcCoA increased the rate to 3.1 ±0.93 vs 2.4 ±0.52 nmoles Ac‐Asp/mg protein (p&lt; 0.05). Finally, using 1 mM AcCoA, N‐acetylation increased to 7.23 ±2.69 vs 5.11 ±0.79 nmoles Ac‐Asp/mg protein (p&lt; 0.01). Both NAT1 and NAT2 catalyzed the Put N‐acetylation. For NAT1 in the presence of 100 μM of AcCoA, we observed the formation of 0.19 ±0.03 nmoles Ac‐Put/mg protein in NAT1*4, and 0.108 ±0.02 nmoles Ac‐Put/mg protein in NAT1*14 allele (p&lt; 0.05). Using 300 μM of AcCoA, 0.27 ±0.02 in NAT1*4 vs 0.14 ±0.3 nmoles Ac‐Put/mg protein in NAT1*14 (p&lt; 0.05). Finally, 1 mM of AcCoA yielded 0.43 ±0.03 vs 0.23 ±0.03 nmoles Ac‐Put/mg protein, respectively (p&lt; 0.05). Finally, for NAT2 and Put N‐acetylation, our results show that the reference allele produces 0.26 ±0.03 vs 0.16 ±0.04 nmoles Ac‐Put/mg protein in the slow (NAT2*5B) allele when we used 100 μM of AcCoa (p&lt; 0.05), 0.3 ±0.03 and 0.22 ±0.02 nmoles Ac‐Put/mg protein respectively when we used 300 μM of AcCoA; and 0.4 ±0.03 vs 0.3 ±0.02 nmoles Ac‐Put/mg protein respectively when we used 1 mM AcCoA. In conclusion, these results show that NAT1 and NAT2 are capable of the N‐acetylation of endogenous compounds like Asparagine and Putrescine. Moreover, this metabolic reaction is dependent of the AcCoA present and influenced by the genetic polymorphisms. Future studies will help us understand the implications of the N‐acetylation of these compounds in cellular processes like cancer cell progression.

HLA-B27 may modulate the interaction between ERAP1 polymorphisms and smoking in ankylosing spondylitis patients.

BackgroundAnkylosing spondylitis (AS) is an autoimmune disease that affects the enthesis and synovial membrane of the spine, the sacroiliac vertebrae and peripheral joints. Genetic susceptibility to AS is mainly due to the presence of the HLA-B*27 (B27) allele, and endoplasmic reticulum aminopeptidase-1 (ERAP-1) plays a key role in antigen processing and presentation to HLA class I molecules. Tobacco consumption is one of the main environmental factors involved in the pathogenesis of various diseases, including AS. The objective of the present study was to evaluate the association and the interactive effects of variants of the ERAP1 gene with smoking in modulating the risk of AS. Methods and resultsA case–control study in the Mexican population. The association of two functional variants of the ERAP1 gene (rs30187 and rs27044) in patients with AS was analyzed by the allelic discrimination method using TaqMan probes. B27 was typified by PCR-SSP. The interaction between the variants of ERAP1 and B27 and smoking was assessed using the multifactorial dimensionality reduction (MDR) method. There was no significant association of the two variants of ERAP1 in the cases compared with the controls (P > 0.05); however, a strong interaction between the variants and smoking could be demonstrated, with entropy values of 4.97% for rs30187 and 5.13% for rs27044. In addition, these interaction effects were increased in patients carrying the B27 allele.ConclusionsThe rs30187 and rs27044 variants of the ERAP1 gene appear to potentiate the effect of smoking in patients with AS carrying the B27 allele.

Association of HLA B1 allele profile with pediatric autoimmune liver disease in India

Background and Aim: Association of human leucocyte antigen (HLA) B1 alleles with treatment response in pediatric autoimmune liver disease (pAILD) has been observed in previous studies. The aim of this study was whether HLA B1 alleles are associated with treatment response in Indian children with pAILD.

CYP3A4 *1B Gene Polymorphism in Coronary Artery Disease Patients with Obesity Undergoing Statin Treatment

Objective: Coronary artery disease (CAD) is one of the leading causes of morbidity and mortality worldwide and statins are frequently prescribed in the treatment of CAD to help lower blood cholesterol levels. Since the main enzyme involved in the metabolism of statins is CYP3A4, we aimed to investigate the effect of CYP3A4 * 1B genotypes on plasma lipid profile in Turkish cardiovascular disease subjects with and without obesity taking statin. Materials and Methods: The study group consisted of 85 cardiovascular disease patients who were prescribed statins and had routine biochemical analysis data. Polymerase chain reaction followed by restriction fragment length polymorphism (PCR-RFLP) assay was performed for genotyping of CYP3A4 *1B (rs2740574) polymorphism. Results: Genotype distribution of CYP3A4 *1B polymorphism was found for homozygous wild (AA) and homozygous polymorphic (GG) genotypes as 94.1% and 5.9%, respectively. We did not detect patients with heterozygous genotype in our study group. We found that the mean LDL-c, TG and TC levels were higher in patients with CYP3A4 *1B GG compared to the AA genotype. The frequency of CYP3A4 *1B GG genotype frequency (9.5%) was detected higher in the obese patients compared to the non-obese patients (7.7%) (χ2=0.037, p=0.85). Conclusions: Our results demonstrate that CYP3A4 *1B homozygous polymorphic genotype distribution tends to be higher in obese patients compared to non-obese patients with cardiovascular disease which may point to *1B allele having a slight effect on serum lipids during statin therapy. Additional studies with higher samples are needed for evaluating the role of CYP3A4 *1B on lipids in patients under statin therapy.

Contribution of Arab countries to Behçet disease research: a PubMed-based bibliometric and altmetric analysis.

Behçet's disease (BD), a rare multisystemic disorder, has an unknown etiology. Interactions between genetic and environmental factors play a major role in this disorder. Human leukocyte antigen B51 allele is the strongest risk factor for the development of Behçet disease. The high prevalence of BD in the Arab world makes it necessary to undergo local research and publications, to target particular genetic, geographical, or even cultural risk factors. This study aims to assess the numerical contribution of the Arab world to research on Behçet disease. Using the PubMed platform, the number of BD-related publications from 2005 to 2019 was assessed for all 22 Arab countries, and countries having the highest prevalence of the disease. Number of publications on BD was normalized to the average population size and GDP for each Arab country. From 2005 to 2019, Arab countries published 198 articles related to BD. This accounts for 0.1% of the total number of BD-related articles published in this period (4170). A significant, positive correlation of moderate strength exists between the number of publications and the average population, while a non-significant, positive correlation of week strength exists between the number of publications and GDP. Concerning the top 15 countries according to Behçet disease prevalence, Turkey had the greatest number of articles, while the USA had the highest ratio of publications per prevalence. The high prevalence of BD in Arabic countries was faced by paradoxically low research activity in this field. Arab countries are lagging behind in the field of Behçet disease-related research, which highlights the need for improving research productivity.

Interaction between CETP polymorphism and dietary insulin index and load in relation to cardiovascular risk factors in diabetic adults

Gene–diet interactions may play an important role in the inter individual diversity observed in on cardiovascular disease (CVD) risk factors. Therefore, in the current study, we examined the interaction of CETP TaqB1 polymorphism with dietary insulin index and load (DII and DIL), in altering on CVD risk factors among type 2 diabetes mellitus (T2DM). In this cross-sectional study, blood samples were collected from 220 type 2 diabetic patients (134 females and 86 male) with a mean age of 52.24 years in Tehran, Iran. DIL and DII were obtained via validated food-frequency questionnaire (FFQ). Taq1B polymorphism was genotyped by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Biochemical markers including total cholesterol (TC), low-density lipoprotein (LDL), high-density lipoprotein (HDL), triglyceride (TG), superoxide dismutase (SOD), C-reactive protein (CRP), total antioxidant capacity (TAC), pentraxin-3 (PTX3), isoprostaneF2α (PGF2α). interleukin 18 (IL18), leptin and ghrelin were measured by standard protocol. Patients with B1B1 genotype had lower lipid profiles include LDL/HDL (P < 0.001) and TG (P = 0.04) when they consumed diets higher on the DIL and DII index. Moreover, carriers of B2B2 genotype who were in the last tertile of DIL had higher antioxidant and inflammatory markers include SOD (P = 0.01), PGF2α (P = 0.04) and CRP (P = 0.02). Further, a significant interaction between CETP TaqB1 and DII was shown in terms of WC (P = 0.01), where the highest WC were observed in B2B2 genotype carriers following a DII score. However, the highest inflammatory and antioxidant markers include CRP (P = 0.04), TAC (P = 0.01), SOD (P = 0.02), and PGF2α (P = 0.02) were observed in B2B2 genotype carriers when they consumed diets higher on the DII index. Based on the current study, it could be proposed that CETP polymorphism may be associated with CVD risk factors in T2DM patients with high following insulin indices, including DII and DIL. It seems that CETP Taq1B polymorphism can invert the result produced by insulin. This conclusion illustrates that the CETP Taq1B B1 allele could counteract the CVD risk induced by high DII and DIL.

Comparison of Next-Generation Sequencing-Based Human Leukocyte Antigen Typing with Clinical Flow Cytometry and Allele-Specific PCR Melting Assays for HLA-B27 Genotyping.

Due to the strong association between ankylosing spondylitis and Human Leukocyte Antigen (HLA)-B27, accurate identification of HLA-B27 is important in the diagnosis of patients with suspected spondyloarthritides. For this study, we compared a high-resolution HLA-B typing method to the clinical flow cytometry and allele-specific PCR melting assays to determine clinical benefits of high-resolution testing. Residual clinical samples submitted for HLA-B27 testing by flow cytometry were tested by single-locus HLA-B genotyping using next-generation sequencing (NGS), and PCR with melting curve analysis, currently used as a reflex test for indeterminate flow cytometry results. Fifty out of the 51 samples (98%) positive by flow cytometry confirmed as HLA-B27 positive by PCR melting assay and by NGS. The sample that did not confirm was genotyped as HLA-B*07:02. All the samples negative by flow cytometry were confirmed as HLA-B27 negative by both PCR melting assay and NGS. For the group that was indeterminate by flow cytometry, 84.5% (n = 49) typed as positive for HLA-B27, while 15.5% (n = 9) were negative for HLA-B27 but positive for HLA-B*07:02. NGS was the only method able to distinguish between pathogenic and nonpathogenic HLA-B27 variants, in contrast to the flow cytometry or the PCR melting assays. Single-locus NGS is superior to flow cytometry and PCR melting assay for the unambiguous identification of HLA-B27 variants, and uniquely able to distinguish between pathogenic and nonpathogenic B27 alleles. Due to its high accuracy, it may be a feasible superior alternative to flow cytometry and traditional molecular methods for clinical HLA-B27 testing.

Relevance of genetic polymorphisms of the human cytochrome P450 3A4 in rivaroxaban-treated patients

Rivaroxaban is an anticoagulant drug that prevents forming of blood clots. In addition, it can be administered to prevent and treat thrombotic diseases such as atrial fibrillation, cardiac arrhythmia, heart valve disease, orthopedic surgery, and thrombophilia to reduce the risk of thrombosis. Various factors such as age, gender, diet, medications, and genetic factors effectively determine the dose of rivaroxaban. Genetic variability in drug-metabolizing enzymes, including the cytochrome P450 (CYP450) enzymes and especially CYP3A4, has been associated with rivaroxaban response. The current study aimed to identify the frequency of CYP3A4 common polymorphisms, as well as their association with rivaroxaban response in 100 patients of Arab descent (48.6% female). CYP3A4 gene polymorphisms were examined by the PCR-RFLP method, and the findings were analyzed by SPSS 16 software and t-test. The frequency of CYP3A4*1B/*1B, CYP3A4*1B/*1A, CYP3A4*1B/*1C, and CYP3A4*1A/*1C was 67.35%, 10.64%, 19.12% and 2.89%, respectively. According to our results, CYP3A4 *1B/*1B genotype was the most common, and patients with CYP3A4*1B/*1B alleles needed a higher daily dose of rivaroxaban than *1B/*1A, *1B/*1C, and *1A/*1C carriers (9.57 ± 1.54 mg/day, P=0.015). Therefore, according to the results, CYP3A4 gene polymorphism has an important effect on the dose of rivaroxaban required to maintain the International Normalized Ratio (INR) in the range of 2-3.

Dexketoprofen Pharmacokinetics is not Significantly Altered by Genetic Polymorphism.

Dexketoprofen is the (S)-(+)-enantiomer of racemic ketoprofen, a nonsteroidal anti-inflammatory drug used for the management of different types of pain. To the best of our knowledge, no article was published to date on dexketoprofen pharmacogenetics. Thence, in this work, we aimed to explore the influence of sex, race and several single nucleotide polymorphisms (SNPs) in genes encoding metabolizing enzymes (e.g. CYP or UGT) or transporters (e.g., ABC or SLC) in the pharmacokinetics and safety of dexketoprofen to explore whether dosing adjustments based on genetic polymorphism would be beneficial for its prescription. For this regard, 85 healthy volunteers enrolled in three bioequivalence clinical trials were genotyped for 46 SNPs in 14 genes. Women showed lower AUC adjusted by dose/weight (AUC/DW) and higher Vd/F and Cl/F than men (p < 0.05 in univariate and multivariate analysis). CYP1A2*1B allele, CYP2B6 IM/PM and CYP2D6 IM/PM phenotypes were related to drug accumulation (AUC/DW or Cmax/DW) compared to the CYP1A2*1 allele, CYP2B6 NM/RM and CYP2D6 NM/UM phenotypes (p < 0.05 in the univariate analysis). ABCB1 C1236TT, C3435TT and G2677A/TA/T alleles were related to lower Cmax/DW compared to C, C, and G alleles (p < 0.05 in univariate and multivariate analysis). ABCB1 C1236TT allele was also related to lower AUC/DW (p < 0.05 in multivariate analysis). The remaining studied transporter genes (ABCC2, SLC22A1, and SLCO1B1) and metabolizing enzyme genes (CYP3A5, CYP2C19, CYP2C9, CYP2C8, CYP3A4, CYP2A6, and UGT1A1) were unrelated to dexketoprofen pharmacokinetic variability. We conclude that dexketoprofen pharmacokinetics can be influenced by several polymorphisms, although there is not a clear pharmacogenetic predictor that would justify individualization of therapy based on its genotyping. Further studies should be conducted to confirm the role of SNPs in CYP2B6, CYP2D6, CYP1A2 and ABCB1 on the pharmacokinetic variability of dexketoprofen. Current evidence on dexketoprofen pharmacogenetics does not justify its inclusion in pharmacogenetic guidelines.

Analysis of Genetic Variations in Poly Gene Sequences in Dengue Virus 2 Using In-Silico RFLP

Dengue hemorrhagic fever (DHF) is a disease caused by Dengue virus transmitted to humans through infected Aedes aegypti and Ae. Albopictus . Dengue virus classified into 4 serotypes, including DEN-1, DEN-2, DEN-3, and DEN-4. The genomes of the four dengue viruses share about 65% similarities, the rest is a genetic variation that differentiates between serotypes. Genetic variations also occur even within one serotype. This study aimed to analyse genetic variation in envelope protein E ( POLY ) gene sequences in Dengue Virus 2 NCBI PopSet 1760494694 using in-silico RFLP by free bioinformatic tools on internet. The restriction enzymes used were Afe I and Apa LI. The results of the in-silico RFLP in this study showed that there were genetic variations in the recognition site of the AfeI enzymes (A1 allele and A2 allele) and ApaLI (B1 allele and B2 allele) in 18 DNA sequences of the POLY gene for Dengue 2 virus NCBI PopSet 1760494694.