Single Nucleotide Polymorphism Analysis Research Articles

The Mechanism Study of Single Nucleotide Polymorphism rs3094165 Regulating the Progression of Hepatocellular Carcinoma via Modulating NADH Dehydrogenase Ubiquinone Fe–S Protein-1

Hepatocellular carcinoma (HCC) is a major contributor to global cancer-related mortality, under-scoring the urgent need to identify effective prognostic markers. Single nucleotide polymorphisms (SNPs) play an increasingly important role in predicting the prognosis of patients with HCC. In this study, a cohort of 637 HCC patients was enrolled, and various online databases were comprehensively surveyed to identify SNPs that potentially impact HCC patient survival. The results of the Cox regression analysis demonstrated a significant association between rs3094165 and poor prognosis among patients with HCC. Further PSM analysis was also employed to control potential biases, and the results remained consistent. These findings suggest that SNPs can serve as reliable prognostic markers for HCC patients. Then, we conducted functional experiments to explore the molecular mechanism and confirmed that rs3094165 potentially regulates the progression of HCC by modulating the expression of the NDUFS1. Taken together, our study provides a comprehensive analysis of SNPs associated with HCC prognosis, and highlights the importance of rs3094165 as potential biomarkers for predicting poor prognosis of HCC patients. Our findings also shed light on the influence of rs3094165 on HCC progression by regulating NDUFS1 expression.

Association of Vitamin D Receptor Gene Polymorphisms with Cardiometabolic Phenotypes in Hispanics: A Life Course Approach.

The vitamin D receptor (VDR) is vital for maintaining calcium and phosphate balance and regulating bone metabolism. Recent research has suggested that VDR also plays an essential role in metabolic diseases. Previous studies on non-Hispanic whites have shown that VDR single nucleotide polymorphisms (SNP) are associated with cardiometabolic phenotypes. However, the association between VDR SNPs and cardiometabolic traits in Hispanics remains unclear. This study investigated the association between VDR SNPs and cardiometabolic phenotypic data in self-reported Hispanics (n = 1610) from the Arizona Insulin Resistance registry and Sangre Por Salud Biobank. The study population was predominantly female (66.4%) with a mean age of 40 ± 14 years (n = 121 <18 years) and an average body mass index (BMI) of 29.8 ± 6.3 kg/m2. We performed a genotyping association analysis of VDR SNPs (Taq1-rs731236, Fok1-rs2228570 and Apa1-rs7975232) with cardiometabolic traits using linear regression models. The results showed that Taq1 and Apa1 were strongly associated with systolic blood pressure (SBP) in children (<18 years), while Fok1 was associated with measures of adiposity, including fat mass, waist circumference, and BMI. In age-stratified adult (≥18 years) models, Taq1 was strongly associated with hemoglobin A1c, while Apa1 was associated with BMI and fasting glucose. Fok1 had no significant associations in the adult models. In conclusion, the VDR SNPs were associated with several cardiometabolic phenotypes in this Hispanic sample, but the type and strength of the associations varied by age group.

Strain diversity in Mycobacterium avium subsp. paratuberculosis-positive bovine fecal samples collected in Switzerland.

Paratuberculosis or Johne's disease is a chronic intestinal disease in domestic and wild ruminants. It affects global dairy economy and is caused by Mycobacterium avium subsp. paratuberculosis (MAP). The objective of this study was to analyze strain diversity in MAP-positive fecal samples by using a particular single nucleotide polymorphism (SNP) distinguishing between cattle (C-) and sheep (S-) type MAP and analysis of SNPs within gyrA and gyrB genes differentiating between Types I, II, and III. Moreover, mycobacterial interspersed repetitive unit and variable-number tandem repeat (MIRU-VNTR) analysis using eight established loci was performed. A total of 90 fecal samples from diseased animals presenting diarrhea and/or weight loss, originating from 59 bovine herds across 16 cantons of Switzerland were screened by PCR for the MAP-specific F57 and IS900 genes and were further subtyped. 96.7% and 3.3% of the samples contained C- and S-type MAP, respectively. Ten INRA Nouzilly MIRU-VNTR (INMV) profiles, with a discriminatory index of 0.802, calculated based on 65 epidemiological independent genotypes, were detected: INMV 1 (33.8%), INMV 2 (23.1%), INMV 6 (16.9%), INMV 9 (9.2%), INMV 116 (4.6%), INMV 3 (3.1%), INMV 5 (3.1%) and INMV 72 (1.5%), including two novel INMV profiles, namely INMV 253 (3.1%; S-type III) and INMV 252 (1.5%; C-type). INMV 1, INMV 2, and INMV 6 comprised almost 75% of the F57- and IS900-positive samples. Typing data from 11 herds suggest that there are some herds with intra-herd diversity of genotypes. The results of this study indicate a heterogeneity of MAP in Switzerland.

The XRCC1 and TP53 gene polymorphisms are associated with advanced-stage disease and early distant metastasis at diagnosis in non-small cell lung cancer.

Studies on single nucleotide polymorphisms (SNPs) in non-small cell lung cancer (NSCLC) suggest that DNA repair capacity may have prognostic implications for disease recurrence and survival. However, there is no study investigating the relationship between SNPs and the risk of metastasis at the time of initial diagnosis in patients with NSCLC. This study aimed to investigate the potential predictive value of SNPs in detecting the risk of metastasis at the time of initial diagnosis and poor prognosis in patients with NSCLC. In this prospective cohort study, we evaluated 275 patients with NSCLC. Analysis of SNPs from peripheral blood cells was performed by a polymerase chain reaction. Excision repair cross-complementing group 1 (ERCC1)- Asn118Asn, excision repair cross-complementing group 2 (ERCC2)-Lys751Gln, X-ray repair cross-complementing group 1 (XRCC1)-Arg399Gln, and tumor protein 53 (TP53)-Arg72Pro polymorphisms were evaluated in conjunction with the development of metastasis. The ERCC1 normal genotype, ERCC2 heterozygote genotype, XRCC1 normal genotype, and TP53 normal genotype were associated with a higher stage and more advanced-stage disease at the time of initial diagnosis (P = 0.027, 0.005, <0.001, and 0.006, respectively). Also, XRCC1 normal genotype and TP53 normal genotype were associated with the risk of metastasis at the time of initial diagnosis (P = <0.001 and 0.002, respectively). Moreover, the XRCC1 normal genotype was associated with the risk of brain metastasis at the time of initial diagnosis (P = 0.031). We showed that SNPs are related to a higher stage and more advanced-stage disease at the time of initial diagnosis in patients with NSCLC, and XRCC1 and TP53 gene polymorphisms are associated with the risk of metastasis. These results may contribute to the identification of high-risk groups and may help to earlier diagnosis and treatment in patients with NSCLC.

Mutation analysis of pathogenic non-synonymous single nucleotide polymorphisms (nsSNPs) in WFS1 gene through computational approaches

A single base changes causing a change to the amino acid sequence of the encoded protein, which is defined as non-synonymous single nucleotide polymorphisms (nsSNPs). Many of the nsSNPs can cause disease, and these nsSNPs are considered as pathogenic mutations. In the study, the high-risk nsSNPs of WFS1 and their influence on the structure and function of wolframin protein were predicted by multiple bioinformatics software. We obtained 13 high-risk nsSNPs of WFS1. All the 13 high-risk nsSNPs are highly conserved residues with a conservative score of 9 or 8 and mostly may cause a decrease in protein stability. The high-risk nsSNPs have an important effect on not only amino acid size, charge and hydrophobicity, but also protein's spatial structure. Among these, 11 nsSNPs had been previously published or cited and 2 nsSNPs (G695S and E776K) had not been reported to date. The two novel variants increased or decreased hydrogen bonds. In conclusion, through different computational tools, it is presumed that the mechanism of pathogenic WFS1 nsSNPs should include the changes of physicochemical properties, significant structural changes and abnormal binding with functional partners. We accomplished the computational-based screening and analysis for deleterious nsSNPs in WFS1, which had important reference value and could contribute to further studies of the mechanism of WFS1 related disease. The computational analysis has many advantages, but the results should be identified by further experimental studies in vivo and in vitro.

Characteristics of a Temperature-Sensitive Mutant Strain of Salmonella Enteritidis and Its Potential as a Live Vaccine Candidate.

Salmonella Enteritidis is a common foodborne pathogen transmitted through poultry products, which are its main carriers. Poultry are vaccinated against Salmonella Enteritidis in many countries, despite the absence of clinical symptoms, using commercially available live-attenuated vaccines. We previously constructed a highly attenuated temperature-sensitive (ts) Salmonella Enteritidis mutant, 2S-G10. In the present study, we describe the construction and attenuation-associated characteristics of 2S-G10. We infected 1-day-old chicks with 2S-G10 and the parental strains to evaluate the attenuation. One week after infection, 2S-G10 was not detected in the liver, cecum, or cecal tonsil tissues of the orally inoculated chicks, contrary to the parental strain. This indicates that 2S-G10 was highly attenuated when compared to the parental stain. In vitro experiments revealed the inability of 2S-G10 to grow at the normal body temperature of chickens and invade chicken liver epithelial cells. Moreover, single nucleotide polymorphism (SNP) analysis between the complete genome sequence of 2S-G10 and its parental strain revealed SNPs in bcsE, recG, rfaF, and pepD_1 genes, which are involved in epithelial cell invasion and persistence in host systems, growth, lipopolysaccharide core biosynthesis, and cellular survival under heat stress, respectively. These potential characteristics are consistent with the findings of in vitro experiments. Conclusively, chemical treatment-induced random genetic mutations highly attenuated 2S-G10, implying its potential to be developed as a novel live-attenuated vaccine against Salmonella Enteritidis.

Preeclampsia Susceptibility Assessment Based on Deep Learning Modeling and Single Nucleotide Polymorphism Analysis.

The early diagnosis of preeclampsia, a key outlook in improving pregnancy outcomes, still remains elusive. The present study aimed to examine the interleukin-13 and interleukin-4 pathway potential in the early detection of preeclampsia as well as the relationship between interleukin-13 rs2069740(T/A) and rs34255686(C/A) polymorphisms and preeclampsia risk to present a combined model. This study utilized raw data from the GSE149440 microarray dataset, and an expression matrix was constructed using the RMA method and affy package. The genes related to the interleukin-13 and interleukin-4 pathway were extracted from the GSEA, and their expression levels were applied to design multilayer perceptron and PPI graph convolutional neural network models. Moreover, genotyping for the rs2069740(T/A) and rs34255686(C/A) polymorphisms of the interleukin-13 gene were tested using the amplification refractory mutation system PCR method. The outcomes revealed that the expression levels of interleukin-4 and interleukin-13 pathway genes could significantly differentiate early preeclampsia from normal pregnancy. Moreover, the present study's data suggested significant differences in the genotype distribution, the allelic frequencies and some of the risk markers of the study, in the position of rs34255686 and rs2069740 polymorphisms between the case and control groups. A combined test of two single nucleotide polymorphisms and an expression-based deep learning model could be designed for future preeclampsia diagnostic purposes.

Evaluation of Different SNP Analysis Software and Optimal Mining Process in Tree Species.

Single nucleotide polymorphism (SNP) is one of the most widely used molecular markers to help researchers understand the relationship between phenotypes and genotypes. SNP calling mainly consists of two steps, including read alignment and locus identification based on statistical models, and various software have been developed and applied in this issue. Meanwhile, in our study, very low agreement (<25%) was found among the prediction results generated by different software, which was much less consistent than expected. In order to obtain the optimal protocol of SNP mining in tree species, the algorithm principles of different alignment and SNP mining software were discussed in detail. And the prediction results were further validated based on in silico and experimental methods. In addition, hundreds of validated SNPs were provided along with some practical suggestions on program selection and accuracy improvement were provided, and we wish that these results could lay the foundation for the subsequent analysis of SNP mining.

Genome-wide SNP analyses reveal a substantial gene flow and isolated-genetic structure of sea cucumber Holothuria leucospilota populations in Western Central Pacific

The black sea cucumber Holothuria leucospilota is a commercially exploited species in the Western and Central Pacific region including Australia and Vietnam, where it has been overfished. There is interest to develop captive breeding, sea ranching and restocking programs for H. leucospilota. However, the wide distribution of this species could lead to genetic structure among site, which needs to be considered for responsible genetic management for example, restocking. This is the first study to investigate population genetics in H. leucospilota, between Australia and Vietnam, using single nucleotide polymorphisms (SNPs). The results indicated that there was high gene flow (Nm > 4) and genetic similarities among three Vietnamese populations, which inferred a high panmictic stock structure in Vietnam. Less gene flow (Nm > 1) was indicated between Vietnam and Mooloolaba (Eastern Australia) populations, and there was a significant genetic differentiation among any Vietnamese populations and Mooloolaba population (FST from 0.034 to 0.043; P < 0.05). Surprisingly, there was a major genetic difference (FST > 0.2) and a restricted gene flow (Nm <1) between Darwin (Northern Australia) population and other sea cucumber populations studied (Vietnam and Eastern Australia), which revealed a genetic break/divergence in Darwin. Based on these findings, we can propose that the Vietnamese sea cucumber stocks be considered as a single genetic stock with concordant implications for genetic management. We consider whether the genetic differences in the Darwin stock arise from bottlenecking and are not reflective of adaptive differences. In summary, the results from this study provide basic genetic information on H. leucospilota populations, that would help to design restocking management plans, genetic conservation initiatives and sea ranching programs for H. leucospilota.

Risk factors and molecular epidemiology of bloodstream infections due to carbapenem-resistant Klebsiella pneumoniae

PurposeCarbapenem-resistant Klebsiella pneumoniae (CRKP) is emerging as a worldwide public health concern; however, molecular epidemiological surveillance of clinical CRKP bloodstream infection (BSI) in China is limited. We conducted a retrospective observational study to assess risk factors and the molecular epidemiology of CRKP BSI. MethodsWe reviewed the medical records of enrolled patients to assess risk factors of CRKP BSI. Characteristics of CRKP isolates were analyzed by whole genome sequencing and Kleborate. Evolutionary diversification in CRKP isolates was described through Single Nucleotide Polymorphisms analysis and phylogenetic tree construction. ResultsWe found that prior ICU hospitalization and use of carbapenems were independent risk factors for CRKP BSI. The main CRKP sequence type (ST) and capsular serotype were ST11 and KL64, and KPC-2 was the most prevalent enzyme type of carbapenemase-carrying Klebsiella pneumoniae. The most prevalent aerobactin and yersiniabactin of ST11-CRKP were iuc-1 and ybt9 ICEKp3, as for KL64-CRKP. Phylogenomic analysis showed that the antibacterial resistance genes on plasmids were highly consistent, but the genetic background of the chromosomes was still different. ConclusionsOur findings are important for hospitals, allowing them to limit dissemination of CRKP and optimize antibiotic administration.

Registration of ‘Giant’ forage cowpea

Abstract‘Giant’ (Reg. no. CV‐348, PI 701902) is a southern root‐knot nematode (Meloidgyne incognita race 3 and race 4)–resistant forage cowpea [Vigna unguiculata (L.) Walp.] developed by Texas A&amp;M AgriLife Research at Overton, TX. Giant is intended for use as a warm‐season cover crop, a forage and hay crop, and supplemental browse for white‐tailed deer. Giant is an indeterminate, forage type cowpea that produces biomass from May through September in northeast Texas but also flowers 25 days earlier than ‘Iron &amp; Clay’ cowpea, allowing seed production in northeast Texas before the first average frost date. Single nucleotide polymorphism analysis confirmed the variety mix Iron &amp; Clay as the parental source population for Giant. Forage production of Giant at Overton, TX, in 2019 and 2020 was 5.3 and 6.0 Mg dry matter (DM) ha−1, respectively. Forage production of Giant in 2019 at Prairie and Starkville, MS, was 2.8 and 2.9 Mg DM ha−1, respectively. Protein content of Giant in 2019 at Prairie and Starkville was 21.1 and 21.2%, respectively. Forage production of Giant in 2019 at Chillicothe, TX and Lockett, TX, was 2.6 and 3.6 Mg DM ha−1, respectively. Top growth nitrogen (N) yield of Giant in 2019 at Chillicothe, TX, and Lockett, TX, was 67 and 65 kg N ha−1, respectively. Based on very low nematode reproduction, Giant is rated resistant and partially resistant to southern root‐knot nematode race 3 and race 4, respectively.

Genome-wide association study of copy number variation in flax through the lens of genome integrity

Classical methods for identification of genetic variants associated with certain macroscopic phenotypic traits are, as a rule, limited to analyses of single nucleotide polymorphisms. Copy number variations, and more broadly structural variants may provide a plethora of useful information due to the magnitude of the changes they induce. However, their use in genome-wide association studies is seriously limited mostly due to the uncertainties in their discovery (i.e., failure to resolve an event with nucleotide resolution) by computational algorithms from genomic data. Nevertheless, in certain cases, such analyses are possible and may still yield valuable results. Our recent work has revealed genetic variants (single nucleotide polymorphisms) possibly related to phenotypic traits determining fibre quality. Here, we decided to extend the analyses to structural variants, namely copy number variations. Importantly, we use a novel high-coverage dataset allowing for accurate prediction of copy number variations. Overall, we compiled a list of 41 candidate genes associated with five quantitative phenotypic traits. Furthermore, the genome stability metric developed earlier facilitated stratification of copy number variant loci with regard to their stability. On the whole, our analyses suggest that the genomic regions less resilient to external and internal stresses are more susceptible to changes associated with the studied phenotypic traits.

An In Silico Functional Analysis of Non-Synonymous Single-Nucleotide Polymorphisms of Bovine CMAH Gene and Potential Implication in Pathogenesis.

The sugar molecule N-glycolylneuraminic acid (Neu5Gc) is one of the most common sialic acids discovered in mammals. Cytidine monophospho-N-acetylneuraminic acid hydroxylase (CMAH) catalyses the conversion of N-acetylneuraminic acid (Neu5Ac) to Neu5Gc, and it is encoded by the CMAH gene. On the one hand, food metabolic incorporation of Neu5Gc has been linked to specific human diseases. On the other hand, Neu5Gc has been shown to be highly preferred by some pathogens linked to certain bovine diseases. We used various computational techniques to perform an in silico functional analysis of five non-synonymous single-nucleotide polymorphisms (nsSNPs) of the bovine CMAH (bCMAH) gene identified from the 1000 Bull Genomes sequence data. The c.1271C>T (P424L) nsSNP was predicted to be pathogenic based on the consensus result from different computational tools. The nsSNP was also predicted to be critical based on sequence conservation, stability, and post-translational modification site analysis. According to the molecular dynamic simulation and stability analysis, all variations promoted stability of the bCMAH protein, but mutation A210S significantly promoted CMAH stability. In conclusion, c.1271C>T (P424L) is expected to be the most harmful nsSNP among the five detected nsSNPs based on the overall studies. This research could pave the way for more research associating pathogenic nsSNPs in the bCMAH gene with diseases.

Dissemination of Pseudomonas aeruginosa blaNDM-1-Positive ST308 Clone in Singapore.

Pseudomonas aeruginosa ST308 clone has been reported to carry carbapenemase genes such as blaIMP and blaVIM but has been rarely associated with blaNDM-1. A total of 199 P. aeruginosa ST308 clinical and environmental isolates obtained between April 2019 and November 2020 from a tertiary-care hospital in Singapore were characterized using whole-genome sequencing. In addition, 71 blaNDM-1-positive ST308 whole-genome sequences from two other local tertiary-care hospitals in Singapore and 83 global blaNDM-1-negative ST308 whole-genome sequences in public databases were included to assess phylogenetic relationships and perform genome analyses. Phylogenetic analysis and divergent time estimation revealed that blaNDM-1-positive P. aeruginosa ST308 was introduced into Singapore in 2005 (95 % highest posterior density: 2001 to 2008). Core genome, resistome, and analyses of all local blaNDM-1-positive ST308 isolates showed chromosomal integration of multiple antibiotic resistance genes (ARGs) [aac(3)-Id, aac(6')-Il, aadA6, aadA11, dfrB5, msr(E), floR, sul2, and qnrVC1], which was absent in global blaNDM-1-negative ST308 sequences. Most ARGs and virulence genes were conserved across isolates originating from the three different local hospitals. Close genetic relatedness of the blaNDM-1-positive ST308 clinical and environmental isolates suggests cocirculation between the hospital environment and human hosts with the hospital environment as a potential reservoir. Core genome single nucleotide polymorphism analyses revealed possible clonal transmission of blaNDM-1-positive ST308 isolates between the three hospitals over 7 years. Bloodstream isolates accounted for six of 95 (6.3%) clinical isolates. This study reports the introduction of a pathogenic blaNDM-1-positive P. aeruginosa ST308 more than a decade ago in Singapore and warrants surveillance for wider dissemination. IMPORTANCE P. aeruginosa is a Gram-negative opportunistic pathogen ubiquitously found in the environment and a major cause of nosocomial infections. While the P. aeruginosa ST308 clone has been known to bear blaIMP and blaVIM among global isolates, reports of blaNDM-1-positive P. aeruginosa ST308 are rare. The local blaNDM-1-positive P. aeruginosa ST308 isolates detected in this study appear to be unique to this region, with evidence of chromosomal acquisition of multiple ARGs compared to global blaNDM-1-negative P. aeruginosa ST308 isolates. Surveillance in Singapore and beyond for dissemination is essential to determine whether existing measures are sufficient to control the spread of this ST308 clone.

Phylogeography of Francisella tularensis subspecies holarctica and epidemiology of tularemia in Switzerland.

Tularemia, an endemic disease that mainly affects wild animals and humans, is caused by Francisella tularensis subsp. holarctica (Fth) in Switzerland. The Swiss Fth population consist of multiple different subclades which are distributed throughout the country. The aim of this study is to characterize the genetic diversity of Fth in Switzerland and to describe the phylogeographic relationship of isolates by single nucleotide polymorphism (SNP) analysis. This analysis is combined with human surveillance data from reported cases over the last 10 years and in vitro and in silico antibiotic resistance tests to provide insight into the epidemiology of tularemia in Switzerland. We sequenced the whole genomes of 52 Fth strains of human or tick origin collected in Switzerland between 2009 and 2022 and analyzed together with all publicly available sequencing data of Swiss and European Fth. Next, we performed a preliminary classification with the established canonical single nucleotide polymorphism nomenclature. Furthermore, we tested 20 isolates from all main Swiss clades for antimicrobial susceptibility against a panel of antimicrobial agents. All 52 sequenced isolates from Switzerland belong to major clade B.6, specifically subclades B.45 and B.46, previously described in Western Europe. We were able to accurately reconstruct the population structure according to the global phylogenetic framework. No resistance to clinically recommended antibiotics could be identified in vitro or in silico in the western B.6 strains.

Functional variant rs10175368 which affects the expression of CYP1B1 plays a protective role against breast cancer in a Chinese Han population.

Cytochrome P450 1B1 ( CYP1B1 ) genetic variants are relevant in the pathogenesis of breast cancer. Exploring the relationships between CYP1B1 functional variants and breast cancer could improve our understanding of breast cancer molecular pathophysiology. This is a two-stage hospital-based case-control study of a Chinese Han population. Genotyping was performed to identify candidate gene variants. 3DSNP, ANNOVAR, and RegulomeDB were used to determine functional single nucleotide polymorphisms (SNPs). The relationship between candidate variants and breast cancer risk was evaluated through unconditional logistic regression analysis. The PancanQTL platform was used to perform cis and trans expression quantitative trait loci (eQTL) analysis of positive SNPs. The GSCA platform was then used to compare the gene expression levels of potential target genes between breast cancer tissue and normal tissue adjacent to the cancer. rs10175368-T acted as a protective factor against breast cancer based on an additive model [odds ratio (OR) = 0.722, 95% confidence interval (CI) = 0.613-0.850; P < 0.001], and was identified as a protective factor in the postmenopausal population (OR = 0.601; 95% CI, 0.474-0.764; P < 0.001). eQTL analysis and analysis of differential expression in carcinoma and paracancerous tissues revealed that the expression level of CYP1B1 - AS1 was associated with rs10175368 and that CYP1B1-AS1 had significantly higher expression levels in breast cancer tissues than in paracancerous tissues. We show, for the first time in a Chinese Han population, that the functional variant rs10175368 plays a protective role against breast cancer, especially in the postmenopausal population.

Assessment of plasmids for relating the 2020 Salmonella enterica serovar Newport onion outbreak to farms implicated by the outbreak investigation

BackgroundThe Salmonella enterica serovar Newport red onion outbreak of 2020 was the largest foodborne outbreak of Salmonella in over a decade. The epidemiological investigation suggested two farms as the likely source of contamination. However, single nucleotide polymorphism (SNP) analysis of the whole genome sequencing data showed that none of the Salmonella isolates collected from the farm regions were linked to the clinical isolates—preventing the use of phylogenetics in source identification. Here, we explored an alternative method for analyzing the whole genome sequencing data driven by the hypothesis that if the outbreak strain had come from the farm regions, then the clinical isolates would disproportionately contain plasmids found in isolates from the farm regions due to horizontal transfer.ResultsSNP analysis confirmed that the clinical isolates formed a single, nearly-clonal clade with evidence for ancestry in California going back a decade. The clinical clade had a large core genome (4,399 genes) and a large and sparsely distributed accessory genome (2,577 genes, at least 64% on plasmids). At least 20 plasmid types occurred in the clinical clade, more than were found in the literature for Salmonella Newport. A small number of plasmids, 14 from 13 clinical isolates and 17 from 8 farm isolates, were found to be highly similar (> 95% identical)—indicating they might be related by horizontal transfer. Phylogenetic analysis was unable to determine the geographic origin, isolation source, or time of transfer of the plasmids, likely due to their promiscuous and transient nature. However, our resampling analysis suggested that observing a similar number and combination of highly similar plasmids in random samples of environmental Salmonella enterica within the NCBI Pathogen Detection database was unlikely, supporting a connection between the outbreak strain and the farms implicated by the epidemiological investigation.ConclusionHorizontally transferred plasmids provided evidence for a connection between clinical isolates and the farms implicated as the source of the outbreak. Our case study suggests that such analyses might add a new dimension to source tracking investigations, but highlights the need for detailed and accurate metadata, more extensive environmental sampling, and a better understanding of plasmid molecular evolution.

Phenotypic and genotypic characteristics of Escherichia coli causing bloodstream and abdominal co-infection

Objective: To analyze the phenotypic and genotypic characteristics of Escherichia coli causing bloodstream and abdominal co-infection (CoECO), and provide clues for empirical antibiotics treatment. Methods: The strains of Escherichia coli isolated from blood and abdominal samples in the Department of Laboratory Medicine of the First Medical Center of the PLA General Hospital from 2010 to 2020 were retrospectively analyzed. Mass spectrometer was used to identify all of the strains and the minimum inhibitory concentration (MIC) were detected by VITEK 2 Compact. All isolates were sequenced by 2×150 bp double terminal sequencing strategy on the HiSeq X Ten sequencer (Illumina). After the genome sequence was spliced, the single nucleotide polymorphism (SNP) analysis of the strain sequence was performed using kSNP3 software to clarify the homologous relationship between strains. If the strains isolated from two different parts had high homology, they were regarded as the same strain and the case was with CoECO infection. Meanwhile, the multilocus sequence type (MLST) was determined using PubMLST website and resistant genes were screened by CARD website. Results: A total of 70 cases of CoECO infection were screened, including 45 males and 25 females, and aged (59.2±16.3) years old. The 70 CoECO isolates belonged to 35 sequence types (STs). The most prevalent STs included ST38 (n=6), ST 405 (n=6), ST 1193 (n=6) and ST131 (n=5), and other ST types contained less than 5 strains. The homologous relationship among strains was relatively scattered, presenting a sporadic trend as a whole, and only a few strains had a small-scale outbreak. The CoECO isolates showed significantly resistance to ampicillin (91.4%, 64/70), ampicillin/sulbactam (74.3%, 5 2/70), ceftriaxone (72.9%, 51/70), ciprofloxacin (71.4%, 50/70) and levofloxacin (71.4%, 50/70), and high-sensitivity to piperacillin/tazobactam, carbapenems and amikacin. The most prevalent resistant gene was tet (A/B) (70%, 49/70), followed by blaTEM (58.6%, 41/70), sul1 (55.7%, 40/70), sul2 (54.3%, 38/70), blaCTX-M-14(25.7%, 18/70), blaCTX-M-15(17.1%, 13/70), blaCTX-M-55(15.7%, 11/70), blaCTX-M-64/65(5.7%, 4/70), blaCTX-M-27(4.3%, 3/70), mcr-1 (4.3%, 3/70), blaNDM-5(2.9%, 2/70). Conclusions: CoECO is distributed dispersedly and has no obvious advantage clone. No genotype with obvious advantages was found. Although the strain has a high resistance rate to some antibacterial drugs, the proportion of carrying resistant genes is low, and it has a high sensitivity to some first-line antibacterial drugs.

Development and validation of a multivariable genotype-informed gestational diabetes prediction algorithm for clinical use in the Mexican population: insights into susceptibility mechanisms

IntroductionGestational diabetes mellitus (GDM) is underdiagnosed in Mexico. Early GDM risk stratification through prediction modeling is expected to improve preventative care. We developed a GDM risk assessment model that integrates...

Investigation of Gene Variation Among Non-Alcoholic Fatty Liver Disease Patients in Gaza Strip: A Preliminary Study

The prevalent hepatic presentation of the metabolic syndrome is a non-alcoholic fatty liver disease (NAFLD), one of the most common types of chronic liver illnesses. Patients with NAFLD may develop liver damage depending on their genetic heritage. In this preliminary study, our main aim was to detect the genetic association of p85α (Met326Ile), PNPLA3 (C&gt;G), IL28B275 (A&gt;G), and IL28B860 (C&gt;T) single nucleotide polymorphisms (SNPs) with steatosis and NASH in patients from Gaza Strip. We performed an SNP analysis by RFLP-PCR in 33 cases of steatosis and 28 cases of non-alcoholic steatohepatitis (NASH), in addition to 29 age- and sex-matched controls. We found that only the mutant T allele of IL28B860 was significantly associated with an increased risk of steatosis (P = 0.04). The other studied alleles and genotypes were not significantly associated with increased or decreased risk of steatosis, NASH, or combined steatosis or NASH groups. Among all of the studied variables (age, sex, diabetes, and BMI), only BMI was significantly associated with an increased risk of steatosis as well as NASH. A linkage disequilibrium analysis showed that the association between the two SNPs of IL28B860 and IL28B275 was significant. Having the TG haplotype increased the risk of steatosis by 2.97 fold and the risk of combined steatosis or NASH by 2.44 fold. This haplotype increased the risk of NASH, but the effect was not significant.