scholarly journals Bacterial Genome wide association studies (bGWAS) and transcriptomics identifies cryptic antimicrobial resistance mechanisms in Acinetobacter baumannii

2019 ◽  
Author(s):  
Chandler Roe ◽  
Charles H.D. Williamson ◽  
Adam J. Vazquez ◽  
Kristen Kyger ◽  
Michael Valentine ◽  
...  
Keyword(s):  
Antimicrobial Resistance ◽  
Acinetobacter Baumannii ◽  
Genome Wide Association Study ◽  
Association Studies ◽  
Bacterial Genome ◽  
Genome Wide Association ◽  
Multiple Drug ◽  
Genome Wide Association Studies ◽  
Genome Wide ◽  
A Genome

AbstractAntimicrobial resistance (AMR) in the nosocomial pathogen, Acinetobacter baumannii, is becoming a serious public health threat. While some mechanisms of AMR have been reported, understanding novel mechanisms of resistance is critical for identifying emerging resistance. One of the first steps in identifying novel AMR mechanisms is performing genotype/phenotype association studies. However, performing genotype/phenotype association studies is complicated by the plastic nature of the A. baumannii pan-genome. In this study, we compared the antibiograms of 12 antimicrobials associated with multiple drug families for 84 A. baumannii isolates, many isolated in Arizona, USA. in silico screening of these genomes for known AMR mechanisms failed to identify clear correlations for most drugs. We then performed a genome wide association study (GWAS) looking for associations between all possible 21-mers; this approach generally failed to identify mechanisms that explained the resistance phenotype. In order to decrease the genomic noise associated with population stratification, we compared four phylogenetically-related pairs of isolates with differing susceptibility profiles. RNA-Sequencing (RNA-Seq) was performed on paired isolates and differentially expressed genes were identified. In these isolate pairs, we identified four different potential mechanisms, highlighting the difficulty of broad AMR surveillance in this species. To verify and validate differential expression, amplicon sequencing was performed. These results suggest that a diagnostic platform based on gene expression rather than genomics alone may be beneficial in certain surveillance efforts. The implementation of such advanced diagnostics coupled with increased AMR surveillance will potentially improve A. baumannii infection treatment and patient outcomes.

scholarly journals Prioritization of genes associated with the pathogenesis of leukosis in cattle

2019 ◽  
Vol 22 (8) ◽  
pp. 1063-1069 ◽  
Author(s):  
N. S. Yudin ◽  
N. L. Podkolodnyy ◽  
T. A. Agarkova ◽  
E. V. Ignatieva
Keyword(s):  
Protein Interactions ◽  
Genome Wide Association Study ◽  
Association Studies ◽  
Mammalian Species ◽  
Genome Wide Association ◽  
Farm Animals ◽  
Genome Wide Association Studies ◽  
Protein Protein Interactions ◽  
Genome Wide ◽  
A Genome

Selection by means of genetic markers is a promising approach to the eradication of infectious diseases in farm animals, especially in the absence of effective methods of treatment and prevention. Bovine leukemia virus (BLV) is spread throughout the world and represents one of the biggest problems for the livestock production and food security in Russia. However, recent genome-wide association studies have shown that sensitivity/resistance to BLV is polygenic. The aim of this study was to create a catalog of cattle genes and genes of other mammalian species involved in the pathogenesis of BLV-induced infection and to perform gene prioritization using bioinformatics methods. Based on manually collected information from a range of open sources, a total of 446 genes were included in the catalog of cattle genes and genes of other mammals involved in the pathogenesis of BLV-induced infection. The following criteria were used to prioritize 446 genes from the catalog: (1) the gene is associated with leukemia according to a genome-wide association study; (2) the gene is associated with leukemia according to a case-control study; (3) the role of the gene in leukemia development has been studied using knockout mice; (4) protein-protein interactions exist between the gene-encoded protein and either viral particles or individual viral proteins; (5) the gene is annotated with Gene Ontology terms that are overrepresented for a given list of genes; (6) the gene participates in biological pathways from the KEGG or REACTOME databases, which are over-represented for a given list of genes; (7) the protein encoded by the gene has a high number of protein-protein interactions with proteins encoded by other genes from the catalog. Based on each criterion, a rank was assigned to each gene. Then the ranks were summarized and an overall rank was determined. Prioritization of 446 candidate genes allowed us to identify 5 genes of interest (TNF,LTB,BOLA-DQA1,BOLA-DRB3,ATF2), which can affect the sensitivity/resistance of cattle to leukemia.

scholarly journals Panton-Valentine leucocidin is the key determinant of Staphylococcus aureus pyomyositis in a bacterial genome-wide association study

2018 ◽  
Author(s):  
Bernadette C Young ◽  
Sarah G Earle ◽  
Sona Soeng ◽  
Poda Sar ◽  
Varun Kumar ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Association Study ◽  
Genome Wide Association Study ◽  
Association Studies ◽  
Bacterial Genome ◽  
Strong Relationship ◽  
Genome Wide Association ◽  
Tropical Regions ◽  
Genome Wide ◽  
A Genome

AbstractPyomyositis is a severe bacterial infection of skeletal muscle, commonly affecting children in tropical regions and predominantly caused by Staphylococcus aureus. To understand the contribution of bacterial genomic factors to pyomyositis, we conducted a genome-wide association study of S. aureus cultured from 101 children with pyomyositis and 417 children with asymptomatic nasal carriage attending the Angkor Hospital for Children in Cambodia. We found a strong relationship between bacterial genetic variation and pyomyositis, with estimated heritability 63.8% (95% CI 49.2-78.4%). The presence of the Panton-Valentine leucocidin (PVL) locus increased the odds of pyomyositis 130-fold (p =10-17.9). The signal of association mapped both to the PVL-coding sequence and the sequence immediately upstream. Together these regions explained > 99.9% of heritability. Our results establish staphylococcal pyomyositis, like tetanus and diphtheria, as critically dependent on expression of a single toxin and demonstrate the potential for association studies to identify specific bacterial genes promoting severe human disease.

scholarly journals Fine Mapping of Intracranial Aneurysm Susceptibility Based on a Genome-wide Association Study

2021 ◽  
Author(s):  
Eun Pyo Hong ◽  
Dong Hyuk Youn ◽  
Bong Jun Kim ◽  
Jun Hyong Ahn ◽  
Jeong Jin Park ◽  
...  
Keyword(s):  
Intracranial Aneurysm ◽  
Fine Mapping ◽  
Bayes Factor ◽  
Genome Wide Association Study ◽  
Association Studies ◽  
Genome Wide Association ◽  
Genome Wide Association Studies ◽  
Network Analyses ◽  
Genome Wide ◽  
A Genome

Abstract In addition to conventional genome-wide association studies (GWAS), a fine-mapping is increasingly used to identify the genetic function of variants associated with disease susceptibilities. Here, we used a fine-mapping approach to evaluate the casual variants based on a previous GWAS involving patients with intracranial aneurysm (IA). Fine-mapping analysis was conducted based on the chromosomal data provided by GWAS consisting 250 patients diagnosed with IA and 296 controls using posterior inclusion probability (PIP) and log10 transformed Bayes factor (log10BF). The narrow sense of heritability (h2) explained by each casual variant was estimated. Subsequent gene expression and functional network analyses were used to calculate the transcripts per million (TPM) values. Twenty causal candidate single nucleotide polymorphisms (SNPs) surpassed a genome-wide significance threshold for creditable evidence (log10BF > 6.1). Four SNPs including rs75822236 (R535H, GBA; log10BF = 15.06), rs112859779 (G141S, TCF24; log10BF = 12.12), rs79134766 (A208T, OLFML2A; log10BF = 14.92), and rs371331393 (Q1932X, ARHGAP32; log10BF = 20.88) showed a completed PIP value in each chromosomal region, suggesting a high probability of variant causality associated with IA. Expression in GBA was highly enriched in the whole blood (TPM = 33.13), while TCF24 were rarely expressed in all tissues and cells. No direct interaction was observed between the four casual genes; however, PSAP appeared to be particularly important via indirect correlation between other genes. Our results suggested that four mutations of GBA, TCF24, OLFML2A, and ARHGAP32 were linked to IA susceptibility and pathogenesis. Our approach may promise more informative mutations in the following GWAS.

scholarly journals A Genome-Wide Association Study of Novel Genetic Variants Associated With Anthropometric Traits in Koreans

2021 ◽  
Vol 12 ◽  
Author(s):  
Hye-Won Cho ◽  
Hyun-Seok Jin ◽  
Yong-Bin Eom
Keyword(s):  
Genetic Variants ◽  
Genetic Factors ◽  
Genome Wide Association Study ◽  
Association Studies ◽  
Fat Distribution ◽  
Genome Wide Association ◽  
Genome Wide Association Studies ◽  
Nucleotide Polymorphisms ◽  
Genome Wide ◽  
A Genome

Most previous genome-wide association studies (GWAS) have identified genetic variants associated with anthropometric traits. However, most of the evidence were reported in European populations. Anthropometric traits such as height and body fat distribution are significantly affected by gender and genetic factors. Here we performed GWAS involving 64,193 Koreans to identify the genetic factors associated with anthropometric phenotypes including height, weight, body mass index, waist circumference, hip circumference, and waist-to-hip ratio. We found nine novel single-nucleotide polymorphisms (SNPs) and 59 independent genetic signals in genomic regions that were reported previously. Of the 19 SNPs reported previously, eight genetic variants at RP11-513I15.6 and one genetic variant at the RP11-977G19.10 region and six Asian-specific genetic variants were newly found. We compared our findings with those of previous studies in other populations. Five overlapping genetic regions (PAN2, ANKRD52, RNF41, HGMA1, and C6orf106) had been reported previously but none of the SNPs were independently identified in the current study. Seven of the nine newly found novel loci associated with height in women revealed a statistically significant skeletal expression of quantitative trait loci. Our study provides additional insight into the genetic effects of anthropometric phenotypes in East Asians.

scholarly journals Genome-Wide Association Studies of Somatic Cell Count in the Assaf Breed

Animals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1531
Author(s):  
Yasemin Öner ◽  
Malena Serrano ◽  
Pilar Sarto ◽  
Laura Pilar Iguácel ◽  
María Piquer-Sabanza ◽  
...  
Keyword(s):  
Somatic Cell ◽  
Genome Wide Association Study ◽  
Association Studies ◽  
Significant Snps ◽  
Genome Wide Association ◽  
System Response ◽  
Genome Wide Association Studies ◽  
Nucleotide Polymorphisms ◽  
Genome Wide ◽  
A Genome

A genome-wide association study (GWAS) was performed to identify new single nucleotide polymorphisms (SNPs) and genes associated with mastitis resistance in Assaf sheep by using the Illumina Ovine Infinium® HD SNP BeadChip (680K). In total, 6173 records from 1894 multiparous Assaf ewes with at least three test day records and aged between 2 and 7 years old were used to estimate a corrected phenotype for somatic cell score (SCS). Then, 192 ewes were selected from the top (n = 96) and bottom (n = 96) tails of the corrected SCS phenotype distribution to be used in a GWAS. Although no significant SNPs were found at the genome level, four SNPs (rs419096188, rs415580501, rs410336647, and rs424642424) were significant at the chromosome level (FDR 10%) in two different regions of OAR19. The SNP rs419096188 was located in intron 1 of the NUP210 and close to the HDAC11 genes (61 kb apart), while the other three SNPs were totally linked and located 171 kb apart from the ARPP21 gene. These three genes were related to the immune system response. These results were validated in two SNPs (rs419096188 and rs424642424) in the total population (n = 1894) by Kompetitive Allele-Specific PCR (KASP) genotyping. Furthermore, rs419096188 was also associated with lactose content.

A genome-wide association study of colorectal cancer in Mexican mestizos suggest novel common tumor-risk variants

2020 ◽  
Author(s):  
AUGUSTO Rojas-Martinez ◽  
Valentina Colistro ◽  
Raquel Cruz ◽  
Clara Ruiz ◽  
Inés Quintela ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Latin American ◽  
Genome Wide Association Study ◽  
Association Studies ◽  
Statistical Significance ◽  
Genome Wide Association ◽  
Genome Wide Association Studies ◽  
Autosomal Snps ◽  
Genome Wide ◽  
A Genome

Abstract Background: Genome-wide association studies (GWAS) for colorectal cancer (CRC) have detected high-risk genetic variants associated with CRC in several ethnic groups, but Latin American communities are still underrepresented. The aim was to identify variants related to CRC in an admixed Latin American population. Methods: The study was performed in 831 cases and 881 controls from Mexico, who were genotyped for 1,006,703 autosomal SNPs. Logistic regression was carried out including covariants, such as sex, age and genetic ancestry. Lastly, we performed a sequence-kernel association test (SKAT) to consider the joint effect of several SNPs lying in genes.Results: Eight chromosomal regions reached genome-wide significance level ( p < 5×10 -8 ): 1p36.22, 1p31.1, 1q42.13, 6p22, 7p14.1, 12q24.32, 16q12.2 and 21q22.2 and 63 variants reached borderline statistical significance ( p < 1×10 − 6 ). SKAT analysis detected 13 loci associated with CRC, none of them previously associated with CRC. Conclusions: We found 8 SNPs and 13 loci associated with CRC. These signals may contribute to enrich the panoply of genes involved with CRC. Further analyses remain to be done to validate the associations in other Latin American populations. This study highlights the importance of conducting GWAS in poorly explored admixed populations.

scholarly journals Rapid response to the alpha-1 adrenergic agent phenylephrine in the perioperative period is impacted by genomics and ancestry

2020 ◽  
Author(s):  
Stephane Wenric ◽  
Janina M. Jeff ◽  
Thomas Joseph ◽  
Muh-Ching Yee ◽  
Gillian M. Belbin ◽  
...  
Keyword(s):  
Genome Wide Association Study ◽  
Association Studies ◽  
Clinical Care ◽  
Low Frequency ◽  
Perioperative Period ◽  
Rapid Response ◽  
Genome Wide Association ◽  
Genome Wide Association Studies ◽  
Genome Wide ◽  
A Genome

Abstract The emergence of genomic data in biobanks and health systems offers new ways to derive medically important phenotypes, including acute phenotypes occurring during inpatient clinical care. Here we study the genetic underpinnings of the rapid response to phenylephrine, an α1-adrenergic receptor agonist commonly used to treat hypotension during anesthesia and surgery. We quantified this response by extracting blood pressure (BP) measurements 5 min before and after the administration of phenylephrine. Based on this derived phenotype, we show that systematic differences exist between self-reported ancestry groups: European-Americans (EA; n = 1387) have a significantly higher systolic response to phenylephrine than African-Americans (AA; n = 1217) and Hispanic/Latinos (HA; n = 1713) (31.3% increase, p value < 6e−08 and 22.9% increase, p value < 5e−05 respectively), after adjusting for genetic ancestry, demographics, and relevant clinical covariates. We performed a genome-wide association study to investigate genetic factors underlying individual differences in this derived phenotype. We discovered genome-wide significant association signals in loci and genes previously associated with BP measured in ambulatory settings, and a general enrichment of association in these genes. Finally, we discovered two low frequency variants, present at ~1% in EAs and AAs, respectively, where patients carrying one copy of these variants show no phenylephrine response. This work demonstrates our ability to derive a quantitative phenotype suited for comparative statistics and genome-wide association studies from dense clinical and physiological measures captured for managing patients during surgery. We identify genetic variants underlying non response to phenylephrine, with implications for preemptive pharmacogenomic screening to improve safety during surgery.

scholarly journals Genome-Wide Association Study of Response to Selenium Supplementation and Circulating Selenium Concentrations in Adults of European Descent

2020 ◽  
Author(s):  
Ken Batai ◽  
Mario J Trejo ◽  
Yuliang Chen ◽  
Lindsay N Kohler ◽  
Peter Lance ◽  
...  
Keyword(s):  
Genome Wide Association Study ◽  
Association Studies ◽  
Genome Wide Association ◽  
Genome Wide Association Studies ◽  
Nucleotide Polymorphisms ◽  
European Descent ◽  
Significance Level ◽  
Genome Wide ◽  
A Genome ◽  
Basal Plasma

ABSTRACT Background Selenium (Se) is a trace element that has been linked to many health conditions. Genome-wide association studies (GWAS) have identified variants for blood and toenail Se levels, but no GWAS has been conducted to date on responses to Se supplementation. Objectives A GWAS was performed to identify the single nucleotide polymorphisms (SNPs) associated with changes in Se concentrations after 1 year of supplementation. A GWAS of basal plasma Se concentrations at study entry was conducted to evaluate whether SNPs for Se responses overlap with SNPs for basal Se levels. Methods A total of 428 participants aged 40–80 years of European descent from the Selenium and Celecoxib Trial (Sel/Cel Trial) who received daily supplementation with 200 µg of selenized yeast were included for the GWAS of responses to supplementation. Plasma Se concentrations were measured from blood samples collected at the time of recruitment and after 1 year of supplementation. Linear regression analyses were performed to assess the relationship between each SNP and changes in Se concentrations. We further examined whether the identified SNPs overlapped with those related to basal Se concentrations. Results No SNP was significantly associated with changes in Se concentration at a genome-wide significance level. However, rs56856693, located upstream of the NEK6, was nominally associated with changes in Se concentrations after supplementation (P = 4.41 × 10−7), as were 2 additional SNPs, rs11960388 and rs6887869, located in the dimethylglycine dehydrogenase (DMGDH)/betaine-homocysteine S-methyltransferase (BHMT) region (P = 0.01). Alleles of 2 SNPs in the DMGDH/BHMT region associated with greater increases in Se concentrations after supplementation were also strongly associated with higher basal Se concentrations (P = 8.67 × 10−8). Conclusions This first GWAS of responses to Se supplementation in participants of European descent from the Sel/Cel Trial suggests that SNPs in the NEK6 and DMGDH/BHMT regions influence responses to supplementation.

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