Association of TRAF1/C5 Locus Polymorphisms with Epilepsy and Clinical Traits in Mexican Patients with Neurocysticercosis

ABSTRACT Neurocysticercosis is caused by the establishment of Taenia solium cysts in the central nervous system. Murine cysticercosis by Taenia crassiceps is a useful model of cysticercosis in which the complement component 5 (C5) has been linked to infection resistance/permissiveness. This work aimed to study the possible relevance for human neurocysticercosis of single nucleotide polymorphisms (SNPs) in the C5-TRAF1 region (rs17611 C/T, rs992670 G/A, rs25681 G/A, rs10818488 A/G, and rs3761847 G/A) in a Mexican population and associated with clinical and radiological traits related to neurocysticercosis severity (cell count in the cerebrospinal fluid [CSF cellularity], parasite location and parasite load in the brain, parasite degenerating stage, and epilepsy). The AG genotype of the rs3761847 SNP showed a tendency to associate with multiple brain parasites, while the CT and GG genotypes of the rs17611 and rs3761847 SNPs, respectively, showed a tendency to associate with low CSF cellularity. The rs3761847 SNP was associated with epilepsy under a dominant model, whereas rs10818488 was associated with CSF cellularity and parasite load under dominant and recessive models, respectively. For haplotypes, C5- and the TRAF1-associated SNPs were, respectively, in strong linkage disequilibrium with each other; thus, these haplotypes were studied independently. For C5 SNPs, carrying the CAA haplotype increases the risk of showing high CSF cellularity 3-fold and the risk of having extraparenchymal parasites 4-fold, two conditions that are related to severe disease. For TRAF1 SNPs, the GA and AG haplotypes were associated with CSF cellularity, and the AG haplotype was associated with epilepsy. Overall, these findings support the clear participation of C5 and TRAF1 in the risk of developing severe neurocysticercosis in the Mexican population.

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Association Between Temperament Related Traits and SNPs in the Serotonin and Oxytocin Systems in Merino Sheep

10.21203/rs.3.rs-34713/v1 ◽

2020 ◽

Author(s):

Luoyang Ding ◽

Shane K Maloney ◽

Mengzhi Wang ◽

Jennifer Rodger ◽

Lianmin Chen ◽

...

Keyword(s):

Serotonin Receptor ◽

Emotional Reactivity ◽

Strong Linkage Disequilibrium ◽

Nucleotide Polymorphisms ◽

Behavioural Phenotype ◽

Single Nucleotide ◽

Gene Markers ◽

Merino Sheep ◽

The Central Nervous System ◽

Arena Test

Abstract Background: Animal temperament is defined as the consistent behavioural and physiological differences that are seen between individuals in response to the same stressor. Neurotransmitter systems, like serotonin and oxytocin in the central nervous system, underlie the variation in temperament in humans. The variations like single nucleotide polymorphisms (SNPs) in the genes for tryptophan 5-hydroxylase (TPH2), the serotonin transporter (SLC6A4), the serotonin receptor (HTR2A), or the oxytocin receptor (OXTR) are associated with the behavior phenotypes in human. Thus, the objective of this study was to identify SNPs in TPH2, SLC6A4, HTR2A and OXTR and to test if those variations predict the temperament of Merino sheep. Results: Using ewes from the UWA temperament flock, that has been selected on emotional reactivity for more than 20 generations, eight SNPs (rs107856757, rs107856818, rs107856856 and rs107857156 in TPH2, rs20917091 in SLC6A4, rs17196799 and rs17193181 in HTR2A, and rs17664565 in OXTR) were found to be distributed differently between calm and nervous sheep. These eight SNPs were then genotyped in 260 sheep from a non-selected flock that has never been selected on emotion reactivity, followed by the estimation of the behavioural traits of those 260 sheep using an arena test and an isolation box test. We found that several SNPs in TPH2 (rs107856757, rs107856818, rs107856856 and rs107857156) were in strong linkage disequilibrium, and all were associated with behavioural phenotype in the non-selected sheep. Similarly, rs17196799 in HTR2A was also associated with the behavioural phenotype. Conclusions: We thus conclude that, rs107856856 and rs17196799 could be used as gene markers for the temperament of Merino sheep, with allele C of rs107856856 and allele A of rs17196799 being associated with calm temperament.

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Assessing Genetic Diversity among Brettanomyces Yeasts by DNA Fingerprinting and Whole-Genome Sequencing

Applied and Environmental Microbiology ◽

10.1128/aem.00601-14 ◽

2014 ◽

Vol 80 (14) ◽

pp. 4398-4413 ◽

Cited By ~ 45

Author(s):

Sam Crauwels ◽

Bo Zhu ◽

Jan Steensels ◽

Pieter Busschaert ◽

Gorik De Samblanx ◽

...

Keyword(s):

Genetic Diversity ◽

Dna Fingerprinting ◽

Wine Industry ◽

Nucleotide Polymorphisms ◽

Single Nucleotide ◽

Content Type ◽

Carbon And Nitrogen ◽

Spoilage Yeasts ◽

Off Flavors ◽

Carbon And Nitrogen Metabolism

ABSTRACTBrettanomycesyeasts, with the speciesBrettanomyces(Dekkera)bruxellensisbeing the most important one, are generally reported to be spoilage yeasts in the beer and wine industry due to the production of phenolic off flavors. However,B. bruxellensisis also known to be a beneficial contributor in certain fermentation processes, such as the production of certain specialty beers. Nevertheless, despite its economic importance,Brettanomycesyeasts remain poorly understood at the genetic and genomic levels. In this study, the genetic relationship between more than 50Brettanomycesstrains from all presently known species and from several sources was studied using a combination of DNA fingerprinting techniques. This revealed an intriguing correlation between theB. bruxellensisfingerprints and the respective isolation source. To further explore this relationship, we sequenced a (beneficial) beer isolate ofB. bruxellensis(VIB X9085; ST05.12/22) and compared its genome sequence with the genome sequences of two wine spoilage strains (AWRI 1499 and CBS 2499). ST05.12/22 was found to be substantially different from both wine strains, especially at the level of single nucleotide polymorphisms (SNPs). In addition, there were major differences in the genome structures between the strains investigated, including the presence of large duplications and deletions. Gene content analysis revealed the presence of 20 genes which were present in both wine strains but absent in the beer strain, including many genes involved in carbon and nitrogen metabolism, and vice versa, no genes that were missing in both AWRI 1499 and CBS 2499 were found in ST05.12/22. Together, this study provides tools to discriminateBrettanomycesstrains and provides a first glimpse at the genetic diversity and genome plasticity ofB. bruxellensis.

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Association of non-synonymous SNPs of <i>OPN</i> gene with litter size traits in pigs

Archives Animal Breeding ◽

10.5194/aab-58-317-2015 ◽

2015 ◽

Vol 58 (2) ◽

pp. 317-323 ◽

Cited By ~ 3

Author(s):

T. Kumchoo ◽

S. Mekchay

Keyword(s):

Litter Size ◽

Reproductive Traits ◽

Snp Markers ◽

Strong Linkage Disequilibrium ◽

Nucleotide Polymorphisms ◽

Large White ◽

Single Nucleotide ◽

Pcr Rflp ◽

Polymerase Chain ◽

Acid Exchange

Abstract. Osteopontin (OPN) gene is a secreted phosphoprotein which appears to play a key function in the conceptus implantation, placentation and maintenance of pregnancy in pigs. The objectives of this study were to verify the non-synonymous single nucleotide polymorphisms (SNPs) and their association with litter size traits in commercial Thai Large White pigs. A total of 320 Thai Large White sows were genotyped using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Three SNPs at c.425G> A, c.573T> C and c.881C> T revealed amino acid exchange rates of p.110Ala> Thr, p.159Val> Ala and p.262Pro> Ser, respectively, and were then segregated. These three SNPs were significantly associated with total number born (TNB) and number born alive (NBA) traits. No polymorphisms of the two SNP markers (c.278A> G and c.452T> G) were observed in this study. Moreover, the SNPs at c.425G> A and c.573T> C were found to be in strong linkage disequilibrium. The association of OPN with litter size emphasizes the importance of porcine OPN as a candidate gene for reproductive traits in pig breeding.

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Causal Role of Single Nucleotide Polymorphisms within themprFGene of Staphylococcus aureus in Daptomycin Resistance

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01184-13 ◽

2013 ◽

Vol 57 (11) ◽

pp. 5658-5664 ◽

Cited By ~ 48

Author(s):

Soo-Jin Yang ◽

Nagendra N. Mishra ◽

Aileen Rubio ◽

Arnold S. Bayer

Keyword(s):

Staphylococcus Aureus ◽

Single Nucleotide Polymorphisms ◽

Point Mutations ◽

Nucleotide Polymorphisms ◽

Wild Type ◽

Single Nucleotide ◽

Content Type ◽

Reading Frame ◽

A Charge

ABSTRACTSingle nucleotide polymorphisms (SNPs) within themprFopen reading frame (ORF) have been commonly observed in daptomycin-resistant (DAPr)Staphylococcus aureusstrains. Such SNPs are usually associated with a gain-in-function phenotype, in terms of either increased synthesis or enhanced translocation (flipping) of lysyl-phosphatidylglycerol (L-PG). However, it is unclear if suchmprFSNPs are causal in DAPrstrains or are merely a biomarker for this phenotype. In this study, we used an isogenic set ofS. aureusstrains: (i) Newman, (ii) its isogenic ΔmprFmutant, and (iii) several intransplasmid complementation constructs, expressing either a wild-type or point-mutated form of themprFORF cloned from two isogenic DAP-susceptible (DAPs)-DAPrstrain pairs (616-701 and MRSA11/11-REF2145). Complementation of the ΔmprFstrain with singly point-mutatedmprFgenes (mprFS295LormprFT345A) revealed that (i) individual and distinct point mutations within themprFORF can recapitulate phenotypes observed in donor strains (i.e., changes in DAP MICs, positive surface charge, and cell membrane phospholipid profiles) and (ii) these gain-in-function SNPs (i.e., enhanced L-PG synthesis) likely promote reduced DAP binding toS. aureusby a charge repulsion mechanism. Thus, for these two DAPrstrains, the definedmprFSNPs appear to be causally related to this phenotype.

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Using Mycobacterium tuberculosis Single-Nucleotide Polymorphisms To Predict Fluoroquinolone Treatment Response

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00076-19 ◽

2019 ◽

Vol 63 (7) ◽

Cited By ~ 3

Author(s):

Marva Seifert ◽

Edmund Capparelli ◽

Donald G. Catanzaro ◽

Timothy C. Rodwell

Keyword(s):

Mycobacterium Tuberculosis ◽

Single Nucleotide Polymorphisms ◽

Specific Resistance ◽

Therapeutic Targets ◽

World Health ◽

Population Pharmacokinetic ◽

Nucleotide Polymorphisms ◽

Single Nucleotide ◽

Content Type ◽

Level Increase

ABSTRACT Clinical phenotypic fluoroquinolone susceptibility testing of Mycobacterium tuberculosis is currently based on M. tuberculosis growth at a single critical concentration, which provides limited information for a nuanced clinical response. We propose using specific resistance-conferring M. tuberculosis mutations in gyrA together with population pharmacokinetic and pharmacodynamic modeling as a novel tool to better inform fluoroquinolone treatment decisions. We sequenced the gyrA resistance-determining region of 138 clinical M. tuberculosis isolates collected from India, Moldova, Philippines, and South Africa and then determined each strain’s MIC against ofloxacin, moxifloxacin, levofloxacin, and gatifloxacin. Strains with specific gyrA single-nucleotide polymorphisms (SNPs) were grouped into high or low drug-specific resistance categories based on their empirically measured MICs. Published population pharmacokinetic models were then used to explore the pharmacokinetics and pharmacodynamics of each fluoroquinolone relative to the empirical MIC distribution for each resistance category to make predictions about the likelihood of patients achieving defined therapeutic targets. In patients infected with M. tuberculosis isolates containing SNPs associated with a fluoroquinolone-specific low-level increase in MIC, models suggest increased fluoroquinolone dosing improved the probability of achieving therapeutic targets for gatifloxacin and moxifloxacin but not for levofloxacin and ofloxacin. In contrast, among patients with isolates harboring SNPs associated with a high-level increase in MIC, increased dosing of levofloxacin, moxifloxacin, gatifloxacin, or ofloxacin did not meaningfully improve the probability of therapeutic target attainment. We demonstrated that quantifiable fluoroquinolone drug resistance phenotypes could be predicted from rapidly detectable gyrA SNPs and used to support dosing decisions based on the likelihood of patients reaching therapeutic targets. Our findings provide further supporting evidence for the moxifloxacin clinical breakpoint recently established by the World Health Organization.

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Molecular Surveillance of Drug Resistance of Plasmodium falciparum Isolates Imported from Angola in Henan Province, China

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00552-19 ◽

2019 ◽

Vol 63 (10) ◽

Cited By ~ 1

Author(s):

Ruimin Zhou ◽

Chengyun Yang ◽

Suhua Li ◽

Yuling Zhao ◽

Ying Liu ◽

...

Keyword(s):

Drug Resistance ◽

Plasmodium Falciparum ◽

Antimalarial Drug ◽

Henan Province ◽

Nucleotide Polymorphisms ◽

Combination Therapies ◽

Antimalarial Drug Resistance ◽

Single Nucleotide ◽

Molecular Surveillance ◽

Content Type

ABSTRACT Angola was the main origin country for the imported malaria in Henan Province, China. Antimalarial drug resistance has posed a threat to the control and elimination of malaria. Several molecular markers were confirmed to be associated with the antimalarial drug resistance, such as pfcrt, pfmdr1, pfdhfr, pfdhps, and K13. This study evaluated the drug resistance of the 180 imported Plasmodium falciparum isolates from Angola via nested PCR using Sanger sequencing. The prevalences of pfcrt C72V73M74N75K76, pfmdr1 N86Y184S1034N1042D1246, pfdhfr A16N51C59S108D139I164, and pfdhps S436A437A476K540A581 were 69.4%, 59.9%, 1.3% and 6.3%, respectively. Three nonsynonymous (A578S, M579I, and Q613E) and one synonymous (R471R) mutation of K13 were found, the prevalences of which were 2.5% and 1.3%, respectively. The single nucleotide polymorphisms (SNPs) in pfcrt, pfmdr1, pfdhfr, and pfdhps were generally shown as multiple mutations. The mutant prevalence of pfcrt reduced gradually, but pfdhfr and pfdhps still showed high mutant prevalence, while pfmdr1 was relatively low. The mutation of the K13 gene was rare. Molecular surveillance of artemisinin (ART) resistance will be used as a tool to evaluate the real-time efficacy of the artemisinin-based combination therapies (ACTs) and the ART resistance situation.

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Polymorphisms of IRAK1 Gene on X Chromosome Is Associated with Hashimoto Thyroiditis in Korean Children

Endocrinology ◽

10.1210/endocr/bqaa088 ◽

2020 ◽

Vol 161 (8) ◽

Cited By ~ 1

Author(s):

Hye-Ri Shin ◽

Won Kyoung Cho ◽

In-Cheol Baek ◽

Na Yeong Lee ◽

Yoon Ji Lee ◽

...

Keyword(s):

X Chromosome ◽

Hashimoto Thyroiditis ◽

Categorical Variables ◽

Graves Disease ◽

Strong Linkage Disequilibrium ◽

Nucleotide Polymorphisms ◽

Single Nucleotide ◽

Korean Children ◽

Autoimmune Thyroid ◽

Thyroid Associated Ophthalmopathy

Abstract Autoimmune thyroid disease (AITD) is predominant in females and has been focused on the sexual diploid in immune response. The IL-1 receptor-associated kinase 1 (IRAK1) gene on the X chromosome was recently suggested as strong autoimmune disease-susceptible loci, second to the major histocompatibility complex region. We investigated the frequency of IRAK1 single-nucleotide polymorphisms (SNPs) in children with AITD. In this study, we observed that SNPs of IRAK1 including rs3027898, rs1059703, and rs1059702 in 115 Korean AITD pediatric patients (Graves’ disease = 74 [females = 52/males = 22]; Hashimoto disease [HD] = 41 [females = 38/males = 3]; thyroid-associated ophthalmopathy [TAO] = 40 (females = 27/males = 13); without TAO = 75 (females = 63/males = 12); total males = 25, total females = 90; mean age = 11.9 years) and 204 healthy Korean individuals (males = 104/females = 100). The data from cases and controls were analyzed from separate sex-stratified or all combined by χ 2 test for categorical variables and Student t test for numerical variables. Our study revealed that SNPs of IRAK1-associated HD and without TAO but Graves’ disease and TAO were not found significant. When cases and controls were analyzed by separate sex, we found that rs3027898 AA, rs1059703 AA, and rs1059702 GG showed disease susceptibility in female AITD, HD, and without TAO. Also, all rs3027898, rs1059703, and rs1059702 were found to be in strong linkage disequilibrium (D′ = 0.96-0.98, r2 = 0.83–0.97). The haplotype of 3 SNPs was higher in AITD than in controls (CGA, r2 = 5.42, P = 0.019). Our results suggest that IRAK1 polymorphisms may contribute to the pathogenesis of HD, AITD, and without thyroid-associated ophthalmopathy for females.

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Variation at the von Willebrand Factor (vWF) Gene Locus Is Associated With Plasma vWF:Ag Levels: Identification of Three Novel Single Nucleotide Polymorphisms in the vWF Gene Promoter

Blood ◽

10.1182/blood.v93.12.4277 ◽

1999 ◽

Vol 93 (12) ◽

pp. 4277-4283 ◽

Cited By ~ 74

Author(s):

Angela M. Keightley ◽

Y. Miu Lam ◽

Jolene N. Brady ◽

Cherie L. Cameron ◽

David Lillicrap

Keyword(s):

Single Nucleotide Polymorphisms ◽

Von Willebrand Factor ◽

Gene Locus ◽

Strong Linkage Disequilibrium ◽

Nucleotide Polymorphisms ◽

Polymorphic Variation ◽

Single Nucleotide ◽

Haplotype 1 ◽

Von Willebrand ◽

Willebrand Factor

Abstract Both genetic and environmental factors contribute to the normal population variability of plasma von Willebrand Factor (vWF) levels, however, regulatory mechanisms at the vWF gene locus itself have not yet been identified. We have investigated the association between polymorphic variation in the 5′-regulatory region of the vWF gene and levels of plasma vWF:Ag in a study of 261 group O blood donors. Three novel single nucleotide polymorphisms (SNPs) were identified in the vWF promoter: C/T at -1234, A/G at -1185, and G/A at -1051. These SNPs had identical allele frequencies of 0.36 for the -1234C, -1185A, and -1051G alleles and 0.64 for the -1234T, -1185G, and -1051A alleles and were in strong linkage disequilibrium. In fact, these polymorphisms segregated as two distinct haplotypes: -1234C/-1185A/-1051G (haplotype 1) and -1234T/-1185G/-1051A (haplotype 2) with 12.6% of subjects homozygous for haplotype 1, 40.6% homozygous for haplotype 2, and 42.5% of subjects heterozygous for both haplotypes. Only 4.3% of individuals had other genotypes. A significant association between promoter genotype and level of plasma vWF:Ag was established (analysis of covariance [ANCOVA], P = .008; Kruskal-Wallis test,P = .006); individuals with the CC/AA/GG genotype had the highest mean vWF:Ag levels (0.962 U/mL), intermediate values of vWF:Ag (0.867 U/mL) were observed for heterozygotes (CT/AG/GA), and those with the TT/GG/AA genotype had the lowest mean plasma vWF:Ag levels (0.776 U/mL). Interestingly, when the sample was subgrouped according to age, the significant association between promoter genotype and plasma vWF:Ag level was accentuated in subjects > 40 years of age (analysis of variance [ANOVA], P = .003; Kruskal-Wallis test, P= .001), but was not maintained for subjects ≤ 40 years of age (ANOVA, P > .4; Kruskal-Wallis test, P > .4). In the former subgroup, mean levels of plasma vWF:Ag for subjects with the CC/AA/GG, CT/AG/GA, and TT/GG/AA genotypes were 1.075, 0.954, and 0.794 U/mL, respectively. By searching a transcription factor binding site profile database, these polymorphic sequences were predicted to interact with several transcription factors expressed in endothelial cells, including Sp1, GATA-2, c-Ets, and NFκB. Furthermore, the binding sites at the -1234 and -1051 SNPs appeared to indicate allelic preferences for some of these proteins. Electrophoretic mobility shift assays (EMSAs) performed with recombinant human NFκB p50 showed preferential binding of the -1234T allele (confirmed by supershift EMSAs), and EMSAs using bovine aortic endothelial cell (BAEC) nuclear extracts produced specific binding of a nuclear protein to the -1051A allele, but not the -1051G allele. These findings suggest that circulating levels of vWF:Ag may be determined, at least in part, by polymorphic variation in the promoter region of the vWF gene, and that this association may be mediated by differential binding of nuclear proteins involved in the regulation of vWF gene expression.

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Genomic Epidemiology of a Protracted Hospital Outbreak Caused by a Toxin A-Negative Clostridium difficile Sublineage PCR Ribotype 017 Strain in London, England

Journal of Clinical Microbiology ◽

10.1128/jcm.00648-15 ◽

2015 ◽

Vol 53 (10) ◽

pp. 3141-3147 ◽

Cited By ~ 28

Author(s):

M. D. Cairns ◽

M. D. Preston ◽

T. D. Lawley ◽

T. G. Clark ◽

R. A. Stabler ◽

...

Keyword(s):

Clostridium Difficile ◽

De Novo ◽

University Hospital ◽

Nucleotide Polymorphisms ◽

Single Nucleotide ◽

Conjugative Transposon ◽

Content Type ◽

Genomic Epidemiology ◽

Hospital Outbreak ◽

Nosocomial Diarrhea

Clostridium difficileremains the leading cause of nosocomial diarrhea worldwide, which is largely considered to be due to the production of two potent toxins: TcdA and TcdB. However, PCR ribotype (RT) 017, one of five clonal lineages of human virulentC. difficile, lacks TcdA expression but causes widespread disease. Whole-genome sequencing was applied to 35 isolates from hospitalized patients withC. difficileinfection (CDI) and two environmental ward isolates in London, England. The phylogenetic analysis of single nucleotide polymorphisms (SNPs) revealed a clonal cluster of temporally variable isolates from a single hospital ward at University Hospital Lewisham (UHL) that were distinct from other London hospital isolates.De novoassembled genomes revealed a 49-kbp putative conjugative transposon exclusive to this hospital clonal cluster which would not be revealed by current typing methodologies. This study identified three sublineages ofC. difficileRT017 that are circulating in London. Similar to the notorious RT027 lineage, which has caused global outbreaks of CDI since 2001, the lineage of toxin-defective RT017 strains appears to be continually evolving. By utilization of WGS technologies to identify SNPs and the evolution of clonal strains, the transmission of outbreaks caused by near-identical isolates can be retraced and identified.

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Quantitative Analysis of Single-Nucleotide Polymorphism for Rapid Detection of TR34/L98H- and TR46/Y121F/T289A-Positive Aspergillus fumigatus Isolates Obtained from Patients in Iran from 2010 to 2014

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.02326-15 ◽

2015 ◽

Vol 60 (1) ◽

pp. 387-392 ◽

Cited By ~ 11

Author(s):

Faezeh Mohammadi ◽

Seyed Jamal Hashemi ◽

Jan Zoll ◽

Willem J. G. Melchers ◽

Haleh Rafati ◽

...

Keyword(s):

Single Nucleotide Polymorphism ◽

Quantitative Analysis ◽

Single Nucleotide Polymorphisms ◽

Aspergillus Fumigatus ◽

Tandem Repeat ◽

Promoter Region ◽

Nucleotide Polymorphisms ◽

Nucleotide Polymorphism ◽

Single Nucleotide ◽

Content Type

ABSTRACTWe employed an endpoint genotyping method to update the prevalence rate of positivity for the TR34/L98H mutation (a 34-bp tandem repeat mutation in the promoter region of thecyp51Agene in combination with a substitution at codon L98) and the TR46/Y121F/T289A mutation (a 46-bp tandem repeat mutation in the promoter region of thecyp51Agene in combination with substitutions at codons Y121 and T289) among clinicalAspergillus fumigatusisolates obtained from different regions of Iran over a recent 5-year period (2010 to 2014). The antifungal activities of itraconazole, voriconazole, and posaconazole against 172 clinicalA. fumigatusisolates were investigated using the European Committee on Antimicrobial Susceptibility Testing (EUCAST) broth microdilution method. For the isolates with an azole resistance phenotype, thecyp51Agene and its promoter were amplified and sequenced. In addition, using a LightCycler 480 real-time PCR system, a novel endpoint genotyping analysis method targeting single-nucleotide polymorphisms was evaluated to detect the L98H and Y121F mutations in thecyp51Agene of all isolates. Of the 172A. fumigatusisolates tested, the MIC values of itraconazole (≥16 mg/liter) and voriconazole (>4 mg/liter) were high for 6 (3.5%). Quantitative analysis of single-nucleotide polymorphisms showed the TR34/L98H mutation in thecyp51Agenes of six isolates. No isolates harboring the TR46/Y121F/T289A mutation were detected. DNA sequencing of thecyp51Agene confirmed the results of the novel endpoint genotyping method. By microsatellite typing, all of the azole-resistant isolates had genotypes different from those previously recovered from Iran and from the Dutch TR34/L98H controls. In conclusion, there was not a significant increase in the prevalence of azole-resistantA. fumigatusisolates harboring the TR34/L98H resistance mechanism among isolates recovered over a recent 5-year period (2010 to 2014) in Iran. A quantitative assay detecting a single-nucleotide polymorphism in thecyp51Agene ofA. fumigatusis a reliable tool for the rapid screening and monitoring of TR34/L98H- and TR46/Y121F/T289A-positive isolates and can easily be incorporated into clinical mycology algorithms.

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