PCR-based Method Research Articles

Development and Validation of a Duplex RT-qPCR for Detection of Peach Latent Mosaic Viroid and Comparison of Different Nucleic-Acid-Extraction Protocols.

Peach latent mosaic viroid (PLMVd) is an important pathogen that causes disease in peaches. Control of this viroid remains problematic because most PLMVd variants are symptomless, and although there are many detection tests in use, the reliability of PCR-based methods is compromised by the complex, branched secondary RNA structure of the viroid and its genetic diversity. In this study, a duplex RT-qPCR method was developed and validated against two previously published single RT-qPCRs, which were potentially able to detect all known PLMVd variants when used in tandem. In addition, in order to simplify the sample preparation, rapid-extraction protocols based on the use of crude sap or tissue printing were compared with commercially available RNA purification kits. The performance of the new procedure was evaluated in a test performance study involving five participant laboratories. The new method, in combination with rapid-sample-preparation approaches, was demonstrated to be feasible and reliable, with the advantage of detecting all different PLMVd isolates/variants assayed in a single reaction, reducing costs for routine diagnosis.

Evaluation of BioFire Filmarray panel for respiratory pathogens: a demographic and clinical analysis in Istanbul, Turkey

We aimed to analyze the distribution of respiratory pathogens(RP) detected by a multiplex PCR-based method (BioFire Diagnostics, USA) among patients with suspected respiratory tract infections (RTI) and to evaluate the demographic, clinical and radiological characteristics of infected individuals . RP were detected in 1621/6376 (25.4%) of the samples in the years 2018-2020. Rhinovirus/enterovirus (RV/EV) were the most commonly detected pathogens (38.1%) followed by influenza A and B viruses (21%) and parainfluenza virus (PIV) (9.5%). Single pathogen was detected in 1361 (84%) and multi pathogens in 260 (16%) of 1621 samples. At least one comorbidity was present in 379 (30.5%) of the patients. Fever was the most common sign followed by cough and dyspnea. Thorax CT was present in 426 of 1243 RP positive patients (34.3%). Any radiological findings was found significantly related for a specific pathogen. No medication was given to 52.9% whereas antibiotics in 35.7% and antivirals in 3.8% of the patients. Film Array panel as a multiplex PCR test is not used rationally in our hospital and results were not dramatically improve management of RTI. A better communication between clinician and microbiologist is required for efficient use of laboratory and rational use of antimicrobials.

Molecular identification and antimicrobial resistance pattern of Nocardia isolated from 14 diseased dogs and cats.

Nocardia are ubiquitous, saprophytic and opportunistic bacteria. They cause a set of pyogenic clinical infections in animals and humans, particularly immunocompromised patients, mostly affecting the skin and respiratory tract, with refractoriness to conventional therapy. The most descriptions of nocardial infections in companion animals involve case reports, and there are scarce case series studies focused on canine and feline nocardiosis in which diagnosis has been based on molecular techniques. We investigated epidemiological aspects, clinical findings, in vitro susceptibility profile, and molecular identification of Nocardia using PCR-based method targeted 16S rRNA gene in twelve dogs and two cats. Among dogs were observed cutaneous lesions (8/12 = 67%), pneumonia (3/12 = 25%), and encephalitis (2/12 = 17%), whereas cats developed cutaneous lesions and osteomyelitis. Nocardia and canine morbillivirus coinfection was described in six dogs (6/12 = 50%). A high mortality rate (6/8 = 75%) was seen among dogs. Three dogs (3/4 = 75%) and one cat (1/2 = 50%) with systemic signs (pneumonia, encephalitis, osteomyelitis), and 83% (5/6) of dogs with a history of concomitant morbillivirus infection died. N. nova (5/12 = 42%), N. cyriacigeorgica (3/12 = 25%), N. farcinica (2/12 = 17%), N. veterana (1/12 = 8%), and N. asteroides (1/12 = 8%) species were identified in dogs, whereas N. africana and N. veterana in cats. Among the isolates from dogs, cefuroxime (12/12 = 100%), amikacin (10/12 = 83%), gentamycin (10/12 = 83%), and imipenem (10/12 = 83%) were the most effective antimicrobials, whereas cefuroxime, cephalexin, amoxicillin/clavulanic acid, imipenem, and gentamycin were efficient against isolates from cats. Multidrug resistance was observed in 36% (5/14) of isolates. We describe a variety of Nocardia species infecting dogs and cats, multidrug-resistant ones, and a high mortality rate, highlighting a poor prognosis of nocardiosis in companion animals, particularly among animals systemically compromised or coinfected by canine morbillivirus. Our study contributes to species identification, in vitro antimicrobial susceptibility profile, clinical-epidemiological aspects, and outcome of natural Nocardia-acquired infections in dogs and cats.

DNA contamination and taxonomic diversity hinder eDNA research on freshwater stingray species: Comment on Lim & Then (2022)

Recently, Lim & Then (2022; Endang Species Res 48:43-50) used an environmental DNA (eDNA) PCR-based method for detecting the presence of an endangered species of freshwater stingray, Fluvitrygon kittipongi (Dasyatidae), in the Pahang River basin, east Peninsular Malaysia. For that, they designed a species-specific pair of primers to amplify a 196 base pair (bp) fragment of the cytochrome c oxidase I (COI) gene. Lim & Then (2022) reported positive detection of this species along an upstream stretch of the Pahang River during the inter-monsoon and the southwest monsoon seasons, with the PCR-amplified eDNA sequences identical to the reference COI sequences of F. kittipongi collected from the Perak River basin, west Peninsular Malaysia. Here, we argue that such positive results are likely the consequence of a DNA contamination because the 196 bp COI fragments of F. kittipongi from the Pahang River and the Perak River differ from each other by 4 nucleotide substitutions. The source of contamination in Lim & Then (2022) could have been the Perak samples the authors handled to develop the primers. We also briefly discuss the potential impact of the presumed co-occurrence of freshwater stingrays of the genus Fluvitrygon in the Pahang River on the specificity of the F. kittipongi-specific primers designed by Lim & Then (2022).

A qPCR-based method to detect the eel parasitic nematode Anguillicola crassus in intermediate and final hosts.

Being able to systematically detect parasitic infection, even when no visual signs of infection are present, is crucial to the establishment of accurate conservation policies. The nematode Anguillicola crassus infects the swimbladder of anguillid species and is a potential threat for eel populations. In North America, naïve hosts such as the American eel Anguilla rostrata are affected by this infection. The accidental introduction of A. crassus following restocking programs may contribute to the actual decline of the American eel in Canada. We present a quantitative real time PCR-based method to detect A. crassus infection in final and intermediate hosts. We tested two protocols on samples from different geographical origins in Canada: 1) a general detection of A. crassus DNA in pools of young final hosts (glass eels) or crustacean intermediate hosts 2) a detection at the individual scale by analyzing swim bladders from elvers, or from adult yellow and silver eels. The DNA of A. crassus was detected in one pool of zooplankton (intermediate host) from the Richelieu River (Montérégie-Québec), as well as in individual swim bladders of 13 elvers from Grande and Petite Trinité rivers (Côte-Nord-Québec). We suggest that our qPCR approach could be used in a quantitative way to estimate the parasitic burden in individual swim bladders of elvers. Our method, which goes beyond most of previous developed protocols that restricted the diagnosis of A. crassus to the moment when it was fully established in its final host, should help to detect early A. crassus infection in nature.

Frequency of unnecessary prenatal diagnosis of hemoglobinopathies: A large retrospective analysis and implication to improvement of the control program.

To determine the frequency and etiology of unnecessary prenatal diagnosis for hemoglobinopathies during 12 years of services at a single university center in Thailand. We conducted a retrospective cohort analysis of prenatal diagnosis during 2009-2021. A total of 4,932 couples at risk and 4,946 fetal specimens, including fetal blood (5.6%), amniotic fluid (92.3%), and chorionic villus samples (2.2%) were analyzed. Identification of mutations causing hemoglobinopathies was carried out by PCR-based methods. Maternal contamination was monitored by analysis of the D1S80 VNTR locus. Among 4,946 fetal specimens, 12 were excluded because of poor PCR amplification, maternal contamination, non-paternity, and inconsistency of the results of the fetuses and parents. Breakdown of 4,934 fetuses revealed 3,880 (78.6%) at risk for the three severe thalassemia diseases, including β-thalassemia major, Hb E-β-thalassemia, and homozygous α0-thalassemia, 58 (1.2%) at risk for other α-thalassemia diseases, 168 (3.4%) at risk for β+-thalassemia, 109 (2.2%) at risk for high Hb F determinants, 16 (0.3%) at risk for abnormal Hbs, and 294 (6.0%) with no risk of having severe hemoglobinopathies. The parents of 409 (8.3%) fetuses had inadequate data for fetal risk assessment. Overall, we encountered unnecessary prenatal diagnostic requests for 645 (13.1%) fetuses. The frequency of unnecessary prenatal diagnosis was high. This could lead to unnecessary risk of complications associated with fetal specimen collection, psychological impacts to the pregnant women and their families, as well as laboratory expenses and workload.

Imported spring onions related to the first recorded outbreak of enteroinvasive Escherichia coli in Denmark, November to December 2021.

Between November and December 2021, the first ever recorded outbreak of enteroinvasive Escherichia coli in Denmark occurred at national scale. We describe the investigation of this outbreak, which was initially recognised in early December 2021. A total of 88 cases (58 female; 30 male) with a median age of 52 years (range: 0-91) were detected by PCR-based diagnostic methods. Case ascertainment was complicated by current culture-free diagnostic procedures, with only 34 cases confirmed by culture, serotyping and whole genome sequencing. Isolates from cases grouped into two serotypes (O136:H7 and O96:H19), which was supported by whole-genome-sequence-phylogeny, also yielding two clusters. Interviews of 42 cases and traceback investigation pointed towards consumption of ready-to-eat salads as the outbreak cause. While the ready-to-eat salads comprised different vegetables, imported spring onions were the only common ingredient and thus the likely source. Environmental investigations failed to recover outbreak strains. This report highlights the value of fast typing (here O-typing) to confirm cases in an outbreak situation. Timely communication and data sharing are also important, and were facilitated by the national collaboration between relevant laboratories, the public health institute and the veterinary and food administration. High hygiene standards for imported fresh vegetables intended for ready-to-eat products are essential.

Investigation of the relationship between IL17A, IL17F and ILR1N polymorphisms and COVID-19 severity: The predictive role of IL17A rs2275913 polymorphism in the clinical course of COVID-19.

Coronavirus disease 2019 (COVID-19) is an infectious respiratory disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Although the mortality rate of the disease has been relatively under control as of 2022, more than 15 million confirmed COVID-19 cases have been detected in Turkey to date, causing more than 100,000 deaths. The clinical manifestation of the disease varies widely, ranging from asymptomatic to acute respiratory distress syndrome causing death. The immune response mechanisms have an important impact on the fine adjustment between healing and enhanced tissue damage. This study aims to investigate the relationship between the variants of the interleukin 1 receptor antagonist (IL1RN), interleukin 17A (IL17A), and interleukin 17F (IL17F) genes and COVID-19 severity. The study population comprised 202 confirmed COVID-19 cases divided into three groups according to severity. The IL1RN variable number of a tandem repeat (VNTR) polymorphism was genotyped by polymerase chain reaction (PCR), and IL17A rs2275913, IL17F rs763780 and rs2397084 polymorphisms were genotyped by the PCR-based restriction fragment length polymorphism method. Statistical analysis revealed a significant association between IL17A rs2275913 variant and COVID-19 severity. The AA genotype and the A allele of IL17A rs2275913 were found significant in the severe group. Additionally, we found a significant relationship between haplotype frequency distributions and severity of COVID-19 for the IL17F rs763780/rs2397084 (p=0.044) and a combination of IL17F rs763780/rs2397084/ IL17A rs2275913 (p=0.04). The CG and CGA haplotype frequencies were significantly higher in the severe group. IL17A rs2275913, IL17F rs763780 and rs2397084 variants appear to have important effects on the immune response in COVID-19. In conclusion, variants of IL17A rs2275913, IL17F rs763780 and rs2397084 may be the predictive markers for the clinical course and potential immunomodulatory treatment options in COVID-19, a disease that has placed a significant burden on our country.

Updates in Laboratory Identification of Invasive Fungal Infection in Neonates.

Invasive fungal infection (IFI) in immunocompromised neonates is significantly associated with high morbidity and mortality and has become the third most common infection in Neonatal Intensive Care Units. The early diagnosis of IFI for neonatal patients is difficult because of the lack of specific symptoms. The traditional blood culture remains the gold standard in clinical diagnosis for neonatal patients but it requires a long duration, which delays treatment initiation. Detections of fungal cell-wall components are developed for early diagnosis but the diagnostic accuracy in neonates needs to be improved. PCR-based laboratory methods, such as real-time PCR, droplet digital PCR, and the cationic conjugated polymer fluorescence resonance energy transfer (CCP-FRET) system, distinguish the infected fungal species by their specific nucleic acids and show a high sensitivity and specificity. Particularly, the CCP-FRET system, which contains a cationic conjugated polymer (CCP) fluorescent probe and pathogen-specific DNA labeled with fluorescent dyes, could identify multiple infections simultaneously. In the CCP-FRET system, the CCP and fungal DNA fragments can self-assemble into a complex with an electrostatic interaction and the CCP triggers the FRET effect under ultraviolet light to make the infection visible. Here, we summarize the recent laboratory methods for neonatal IFI identification and provide a new perspective for early clinical fungal diagnosis.

Designed and validated novel allele-specific primer to differentiate Kernel Row Number (KRN) in tropical field corn.

Kernel row number (KRN) is an important yield component trait with a direct impact on the productivity of maize. The variability in KRN is influenced by the inflorescence meristem size, which is determined by the CLAVATA-WUSCHEL pathway. A CLAVATA receptor-like protein, encoded by the FASCIATED EAR2 (fea2gene), enhances the growth of inflorescence meristem and is thus involved in the determination of KRN. The amplicon sequencing-based method was employed to dissect the allelic variation of the fea2 gene in tropical field corn. Amplicon-based sequencing of AI 535 (Low KRN) and AI 536 (High KRN) was undertaken for the gene fea 2 gene that codes for KRN in maize. Upon multiple sequence alignment of both sequences, A to T transversion at the 1311 position was noticed between Low KRN and High KRN genotypes resulting in different allelic forms of a fea2 gene in tropical maize. An allele-specific primer 1311 fea2.1 was designed and validated that can differentiate High and Low KRN genotypes. Maize has high variability for KRN and is exemplified by the wide values ranging from 8-26 KRN in the maize germpalsm. The sequence-based approach of SNP detection through the use of a specific primer facilitated the detection of variation present in the target trait. This makes it possible to capture these variations in the early generation. In the study, the PCR-based differentiation method described for the identification of desirable high KRN genotypes would augment the breeding programs for improving the productivity of field corn.

Abstract 6109: Multi-site evaluation of novel BRCA1/2 reference materials including large genomic rearrangements

Abstract Mutations in the tumor suppressor BRCA1 and BRCA2 genes can cause cell damage that significantly increases the risk of developing breast, ovarian, prostate, and pancreatic cancers. Large genomic rearrangements (LGRs) are defined as deletions, duplications or insertions; often involving a significant portion of an exon. Usually pathogenic, they have been reported to account for up to 27% of the BRCA1 and 5% of BRCA2 disease-causing mutations with a strong founder effect accounting for about 1/3 of all cancer diagnoses in some populations. Accurate detection of a BRCA1/2 pathogenic variants has immense impact on clinical management of disease including eligibility for PARP inhibitor therapy. However, these LGRs are frequently missed by PCR-based methods and NGS assays that do not detect partial or complete exon losses or gains. Given the difficulty in detecting LGRs, there is a need for improvement of BRCA1/2 testing algorithms including reference materials that incorporate challenging LGRs to support NGS assays that analyze for these mutations. Biosynthetic DNA constructs bearing clinically relevant BRCA1/2 variants including deletions up to 500 bp spanning 2 exons and duplications up to 170 bp, were mixed with purified genomic DNA from the GM24385 human reference cell line at 10% and 50% variant allele frequency (VAF) to represent somatic and inherited BRCA disease states, respectively. The same variants were engineered into GM24385 cells at the desired VAF (>5%) and the cells were formalin fixed and paraffin embedded using a proprietary method to mimic preserved tumor biopsies. In both materials, VAF was measured using digital PCR. The prepared purified gDNA and FFPE materials were sent to multiple clinical laboratories and analyzed using various NGS assays to assess variant detection performance and ensure that the product was compatible with clinical testing workflows. Digital PCR confirmed the presence of all 20 BRCA1 and BRCA2 variants within a 20% range of the target VAF in the purified gDNA material and between 11-23% in FFPE. NGS results were variable but confirmed the presence of most variants. A few variants were detected at very low levels but reported as not detected by the bioinformatic software due to limit of detection. We have successfully developed a reference material to support both BRCA1 and BRCA2 inherited and somatic genetic testing, providing laboratories and assay developers with a tool to challenge and optimize their assay’s detection and quantitation of pathogenic variants by NGS Provided as full process in FFPE format or in purified gDNA, these reference materials include 11 challenging LGRs, which are useful in evaluating the ability of different NGS platforms to detect such variants. This study has highlighted the need for reference materials that contain these challenging genomic alterations to improve genetic testing and ultimately, support PARP inhibitor treatment selection. Citation Format: Dana Ruminski Lowe, Benedicta Forson, Maria Cowen, Matthew G. Butler, Yves Konigshofer, Melissa Berenger, Krystyna Nahlik, Dianren Xia, Catherine Huang, Russell Garlick, Bharathi Anekella. Multi-site evaluation of novel BRCA1/2 reference materials including large genomic rearrangements. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6109.

Genetic contribution of caspase-8 variants and haplotypes to breast cancer risk and prognosis: a case-control study in Iran

PurposeMultiple genome-wide and candidate-gene association studies have been conducted to search for common risk variants of breast cancer. Recent large meta-analyses and consolidating evidence have highlighted the role of the caspase-8 gene in breast cancer pathogenesis. Therefore, this study aimed to identify common variations and haplotypes associated with risk and overall survival of breast cancer with respect to underlying susceptibility variants in the CASP8 gene region in a group of the Iranian population.MethodsIn a case-control study with a total of 1008 samples (455 cases and 553 controls), genotyping of 12 candidate polymorphisms, consisting of rs3834129, rs2037815, rs7608692, rs12990906, rs3769821, rs6435074, rs3754934, rs3817578, rs10931936, rs1045485, rs1045487, and rs13113, were performed using PCR-based methods, including ARMS-PCR, AS-PCR, RFLP-PCR, HRM-PCR, and TaqMan-PCR.Resultsrs3834129, rs3754934, rs12990906, and rs10931936 were associated with the risk and overall survival of breast cancer. Several haplotypes were also identified an associated with a higher risk of breast cancer, including a three-SNP haplotype rs3817578-rs10931936-rs1045485 [p < 0.001, OR = 1.78(1.32–2.41)]. rs3754934-C allele showed an association with a lower risk of death in all patients [p = 0.022; HR = 0.46(0.23–0.89)] and in the hormone-receptor-positive group [p = 0.038; HR = 0.37(0.14–0.95)], as well as CC genotype in the hormone-receptor-positive group [p = 0.002; HR = 0.09(0.02–0.43)].ConclusionThe present study suggests a diagnostic and prognostic role of CASP8 gene variations in breast cancer. The risky haplotypes are likely to have one or more underlying breast cancer susceptibility alleles. Understanding the mode of action of these alleles will aid individual-level risk prediction. It also may help identify at-risk patients to provide them with better surveillance.

The first detection of avian haemosporidia from Culicoides biting midges in Japan, with notes on potential vector species and the transmission cycle.

Biting midges (Ceratopogonidae) are capable of transmitting a variety of pathogens including viruses, trypanosomes and haemosporidia. The majority of Haemoproteus parasites are transmitted by biting midges predominantly of the genus Culicoides and are known to cause significant physical and reproductive impacts on both wild and domestic birds. In Japan, Haemoproteus had been detected from various avian hosts, but not from arthropod vectors. In this study, we investigated the prevalence of avian haemosporidia at an educational forest in central Japan in attempt to reveal possible vector species of Haemoproteus, which would help to better understand the transmission cycle of Haemoproteus within Japan and to develop preventative measures for captive and domestic birds. Biting midges were caught using UV light traps from 2016 to 2018. The collected samples were morphologically identified, and haemosporidian parasites were detected using PCR-based methods. The detected lineages were phylogenetically analyzed and compared with lineages previously detected from birds. Bloodmeal analyses were also carried out for part of the blood-fed individuals. Six Haemoproteus lineages were detected from 17 of 1042 female Culicoides (1.63%), including three species (C. sigaensis, C. arakawae, and C. pictimargo) in which Haemoproteus was detected for the first time. All detected lineages were placed in the subgenus Parahaemoproteus clade and were previously detected from crows of central Japan, strongly suggesting that parasites of these genetic lineages are transmitted between Culicoides and crows. Two Plasmodium lineages were also detected but are thought to be transmitted between Culex mosquitoes and birds of the educational forest based on previous detections. No amplifications were seen in bloodmeal analysis, possibly due to insufficient amount of blood, denaturation via digestion, or insufficient detectability of the used protocol. Haemoproteus DNA was detected from Culicoides for the first time in Japan, suggesting that transmission is possible within the country. These findings highlight the necessity to investigate Culicoides populations and Haemoproteus infections dynamics in Japan. However, vector competence could not be confirmed in this study and further studies are anticipated.

Optimization of annealing temperature for amplification of the exon one region of the HPPD gene in HA1 accession sunflowers

The HPPD gene is one of the genes that is actively involved in the biosynthesis of tocopherol, which is the main component of Vitamin E. Sunflower is raw materials for natural medicine since their oil contains vitamin E. To obtain complete information regarding the whole sequences of the 4-Hydroxyphenylpyruvate Dioxygenase (HPPD) gene in sunflower accession HA1, the exon one region needs to be identified using a PCR-based method. One factor affecting the success rate of PCR is the annealing temperature. The optimum annealing temperature will produce specific target gene products. This study aimed to determine the optimal temperature for amplifying the exon 1 region of the HPPD gene using the PCR method. This research began with primer design activities, followed by in vitro amplification (PCR), then optimization of annealing temperature using gradient PCR. The results showed that the optimum temperature for amplifying fragment one was an annealing temperature of 53 °C, fragment two was at an annealing temperature of 45 °C, and fragment three had an annealing temperature of 57 °C with the expected size of PCR products are 306 bp, 506 bp, and 534 bp respectively.

808 Analysis of Medulloblastomas Subgroups in Pediatric Patients in Latin-America

INTRODUCTION: The 4 groups molecular-based classification of medulloblastomas is widely accepted. However, technology inaccessibility and low-quality formalin-fixed and paraffin-embedded (FFPE) samples, unable its application for most Latin-American cancer centers. METHODS: The goal of this study was to perform a feasibility analysis based on 18 mRNA expression by qPCR integrated with immunohistochemistry (IH) and fluorescent hybridization in situ (FISH) (c-MYC, n-MYC and monosomy 6) for molecular stratification to create an International Treatment Protocol at a low cost for low-income centers. RESULTS: Fifty-four FFPE samples were classified according to histologic and molecular aspects. Classic medulloblastoma was the commonest histology (53.7%), followed by desmoplastic/extensive nodularity (24.1%), NOS (16,7%) and anaplastic (5,6%). IH markers classified patients in three groups (WNT, SHH and non-WNT/non-SHH) in 98% of cases. PCR-based method confirmed results from IH in 81.5%. Additionally, it detected WNT activation in 2 more patients, previously classified as SHH. For both cases, the presence of monosomy 6 confirmed WNT subgroup. The integration of these three techniques resulted in the following frequencies: WNT (13.0%), SHH (38.9%), group 3 (9.3%), group 4 (20.3%) and non-WNT/non-SHH (18.5%). From 40 patients with clinical follow-up available, 3-year overall survival (n = 40) for low, intermediate and high-risk groups were 100%, 60% and 20%, respectively (p &lt; 0.05), based only in molecular criteria, which confirmed the prognostic importance of this method at a low cost. CONCLUSIONS: The prognosis of the treatment of medulloblastomas has changed after novel studies on the molecular subgroups and the introduction of target-based therapy. The current protocol will enable different centers to implement treatment based on the knowledge of molecular subgroups.

Idiopathic Recurrent Pregnancy Loss related toGPIagenein Iraqi patient women

Background: Recurrent pregnancy loss (RPL) is a major concern in the field of reproductive medicine. In particular, idiopathic recurrent pregnancy loss (iRPL) is a condition in which recurrent pregnancy loss occurs without a known cause. Recent studies have shown that genetic factors may contribute to iRPL, and the presence of the 807C/T silent polymorphisms in the GPIa gene has been associated with a higher risk of thrombosis and recurrent abortion.Aim: to determine the allelic frequency of GPIa 807C/T in patients with iRPL and healthy controls in Iraq.Material and Method: A T-ARMS PCR-based method was used to analyze the allelic frequency of GPIa 807C/T in 25 patients with iRPL and 25 healthy controls. The genotypic and allelic frequencies were calculated, and a statistical analysis was performed.Result: The results of this study showed that the allelic frequency for 807C was 48% and 46% in the patient and control groups, respectively. The allelic frequency of 807T was recorded as 52% in the patient group, whereas the control group showed 54%. The patient group's genotypic frequencies were distributed as 16% for 807TT, 12% for 807CC, and 72% for 807CT. On the other hand, the control group reported genotypic frequencies of 32% for 807TT, 24% for 807CC, and 44% for 807CT. Interestingly, the TC heterozygous genotype of the GPIa gene's 807C\T showed a significant increase (P ≤ 0.05) with a risk (OR=3.27) in the patient group against the control.Conclusion: the results of this study suggest that the presence of the GPIa 807C/T polymorphism is associated with a higher risk of iRPL in Iraqi patient women. The findings of this study could be used to develop new diagnostic and therapeutic strategies for iRPL.

FDA-APPROVED MOLECULAR TESTS USED TO DEFINE HUMAN PAPILLOMAVIRUS (HPV) INFECTIONS WHICH CAUSE CERVIX CANCER

Human papillomavirus (HPV) is a non-enveloped, commonly sexually transmitted virus with icosahedral symmetry and double-stranded circular DNA. Its genome, which is about 8 kb in size, encodes early genes (E1-8) and two late structural capsid genes (L1 and L2). Among the genes that play a role in viral pathogenesis, L1, E6, and E7 genes frequently exist. The E6 and E7 viral genes have a significant role in apoptosis inhibition, viral spread, development of squamous intraepithelial lesion (SIL), cell immortalization, neoplastic transformation, and invasive cancer.&#x0D; Demonstration of the relationship between cervical cancer and HPV infections has led to increased interest in this subject and the classification of some HPV genotypes in the high-risk group (HR-HPV) for cervical cancer. Numerous commercial molecular tests have been developed for the identification of HPV genotypes involving different approaches. HPV molecular tests approved by the US Food and Drug Administration (FDA) include Hybrid Capture® 2 (HC2), Cervista™, cobas®, Aptima®, and BD Onclarity™. This article reviews the methodologies, limitations, and commonalities of five FDA-approved tests. The HC2 and Cervista™ tests use non-PCR-based signal amplification methods, while the cobas® and BD Onclarity™ tests use PCR-based target amplification methods. On the other hand, the Aptima® test uses the mRNA transcriptional mediated amplification (TMA) method.&#x0D; Each of these methods used in the diagnosis and follow-up of HPV has its strengths and weaknesses. These HPV molecular tests have high sensitivity and specificity. They are also more automated and repeatable than cytological methods. In addition to these advantages, there are also several limitations. Because of these limitations, molecular tests are no more perfect than cytological tests. This situation shows that these tests should not be used alone in the evaluation of HPV infections and cancer identification. On the contrary, HPV test results should be correlated with cytology or biopsy findings.

Prevalence of Chlamydia trachomatis, Neisseria gonorrhoeae, and Mycoplasma genitalium among Patients with Urogenital Symptoms in Istanbul

Chlamydia trachomatis, Neisseria gonorrhoeae, and Mycoplasma genitalium are the three most commonly reported sexually transmitted bacteria. The present study aimed to investigate the presence of C. trachomatis, N. gonorrhoeae, and M. genitalium in urogenital samples collected from 18-68-year-old Turkish patients who were admitted to the hospital with various urogenital symptoms. A total of 360 patients with symptoms of STD were included in the study. Following DNA extraction by QIAamp Mini Kit, the presence of C. trachomatis, N. gonorrhoeae, and M. genitalium were investigated using multiplex real-time PCR. Causative organisms were identified in 68 (18.9%) of 360 patients. C. trachomatis, N. gonorrhoeae, and M. genitalium were detected in 40 (11.1%), 14 (3.9%), and 28 (7.8%) of the patients, respectively. Patients 21-30 years of age represented more than one-third (37.8%) of positive patients. Of all patients, dual infections of C. trachomatis-M. genitalium, N. gonorrhoeae-C. trachomatis, N. gonorrhoeae-M. genitalium, and triple infection of C. trachomatis-N. gonorrhoeae-M. genitalium were determined in 1.6% (6/360), 1.3% (5/360), 0.2% (1/360), and 0.2% (1/360) of the patients, respectively. In CT-, NG-, and MG-positive patients, different STI agents were also found such as HIV, HBV, HPV, HSV2, T. pallidum, and T. vaginalis. In conclusion, among C. trachomatis, N. gonorrhoeae, and M. genitalium, CT was the most frequently detected bacterial cause of STDs in our hospital at Istanbul. Co-infections, which comprise more than one-fifth of the cases, should not be underestimated. Regular screening and following up of STD agents using multiplex real-time PCR-based diagnostic methods enabling the immediate detection of co-infections are essential for the treatment and primary prevention of STDs.

Comparison between droplet digital PCR and reverse transcription-quantitative PCR methods to measure ecotoxicology biomarkers

Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) is currently the gold-standard technique for detecting and quantifying messenger RNA. However, without proper validation, the method may produce artefactual and non-reproducible cycle threshold values generating poor-quality data. The newer droplet digital PCR (ddPCR) method allows for the absolute quantification of targeted nucleic acids providing more sensitive and accurate measurements without requiring external standards. This study compared these two PCR-based methods to measure the expression of well-documented genes used in ecotoxicology studies. We exposed Mediterranean mussels (Mytilus galloprovincialis) to copper and analyzed gene expression in gills and digestive glands using RT-qPCR and ddPCR assays. A step-by-step methodology to optimize and compare the two technologies is described. After ten-fold serial complementary DNA dilution, both RT-qPCR and ddPCR exhibited comparable linearity and efficiency and produced statistically similar results. We conclude that ddPCR is a suitable method to assess gene expression in an ecotoxicological context. However, RT-qPCR has a shorter processing time and remains more cost-effective.

PCR-Based Method for Authentication of Meat and Processed Meat from Three Commercially Important Catfish Species

PCR-Based Method for Authentication of Meat and Processed Meat from Three Commercially Important Catfish Species